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We took nuts and stoppers from DMM, CAMP, Metolius, and Black Diamond and put them to the test
While all nuts are tapered from top to bottom to some extent each company has its own amount of taper with slightly different shapes that they think is best for specific reasons.
Our climbing experts have been testing the best climbing nuts and stoppers for over 10 years (15 different sets). In this update, we purchased 6 of the best sets and slid them into cracks of all sizes across the United States. We tested each through a wide range of fissures, scar pins, parallel-sided cracks, around blocks, and the like. We used each while ascending wind-blown alpine summits and free climbing sunny cracks in the Valley. After carefully inspecting and testing each set, we gave each an objective performance score. Our recommendations are here to help you find the best nuts and stoppers while saving time at the computer and keeping more money in your wallet.
Work great in pin scars, flares, or other spots where cams don't work
Recessed wires on the top help them fit in tight spots
Works well along secondary axes for more versatility
One of the better options for textured or large-grained rock
REASONS TO AVOID
Cables not super durable
Limited size range
Hader to clean than traditionally tapered nuts
Don't work as well in more parallel-sided cracks
The DMM Alloy Offset nuts are unmatched in ranking because of their overall versatility and how bomber they are in places where other pieces of protection might hold body weight only. The Alloy Offsets are designed to fit in old pin scars and small flares, and they are by far our favorite for these types of placements. This is another reason why the current cam-first generation has transitioned to offset models over more traditionally shaped curved options. Small cams have vastly improved over the years, and most climbers place far more cams than nuts on any given pitch. As a result, climbers tend only to place nuts where cams don't fit, and for this purpose, offset nuts work far better than traditionally shaped models. They also work well in a variety of rock types. With a groove cut on each side, they fit irregular or larger grained rock just as easily as smooth stone.
The DMM Alloy Offsets are okay in more parallel-sided cracks but aren't as good as traditionally-shaped curved models. Their biggest disadvantage is that they're only offered in limited size sets, meaning you need to couple them with another set with smaller sizes to have a complete collection - we recommend the DMM Peenuts. While we think they are worth every penny, these nuts are one of the spendier aluminum models in our review.
At first glance, the limited size range of the DMM Peenuts leads you to think they are a niche piece and that you don't need them. We quickly learned this was not the case. These are some of the most heavily used nuts on our rack. While the largest one is considered a small nut to most, they pair perfectly with the larger DMM Alloy Offsets. Any smaller options are micro-sized pieces that are usually only found on aid racks or placed on very scary technical leads. Other smaller options aren't as strong and might be hard to trust comparatively. We found the size run of the Peenuts to strike a nice balance of having the sizes most used by the majority of trad climbers while maintaining strength and durability. While their aluminum heads don't “bite” as well as brass models, they are way more durable. Also, their cables kink far less than brass nuts because the cables aren't swaged in the head.
The drawback is they need to be paired with a larger nut to make a full-size run for most trad climbs. That said, we found these were the absolute best-performing smaller aluminum nuts regarding durability and strength. We would recommend brass nuts for most aid routes, but we love bringing these on El Cap routes because they're so tough. Their narrow aluminum heads open your eyes to the places they fit, which trad climbers at any level appreciate.
Soft metal deforms to rock, increasing the integrity of placements
Low profile swage lets them squeeze into tight spots
Stiff cables make placing them easier
REASONS TO AVOID
Hard to clean
Brass is less durable
Not for everyday climbing
Cables fixed in the head make wires prone to kinking
Expensive
Tiny brass climbing nuts are considered mandatory for any thinly protected route, from steep El Cap aid lines to Eldorado Canyon sketch-fests, and the DMM HB Brass Offsets are our review team's pick for the best micro nut. Like their aluminum counterparts, they are the most updated version of a tried and true classic. They come in micro sizes, and the large “scope” in the side of their heads accommodates more textured and larger grained rock nicely. The cables are swaged into the head, minimizing extra material and allowing them to slot into the tightest of spaces.
Their brass heads are softer than aluminum models, which have pluses and minuses. On the plus side, the softer brass metal deforms to the rock, facilitating better bite that hopefully translates into better holding power - and something we certainly appreciate in these smaller sizes. The downside is the soft heads get beat up faster and are consistently harder to clean. Their thin cables also require extra care and kink more readily if you clean them carelessly.
Two well-designed orientations make it very versatile
Reasonably priced
Ribbed faces add better “bite” in textured rocks
Durable heads
REASONS TO AVOID
Poor pin scar performance
Set includes the most common sizes but isn't quite a stand-alone size run
Cables kink easier than others
Walks easily
The CAMP Pro Nuts are a new take on an old design. They've taken a classic curved nut, slightly increased the curve and taper, and added grooves/ribs onto the main face for better “bite”. While we didn't find that the ribs help significantly, they certainly don't detract from the Pro Nut's holding power, and in more featured rock, may provide for a slightly better bite. These nuts offer even more curve than most, helping make them one of the most stable nuts out there. The heavily curved design facilitates always having three points of contact on the rock instead of two, which is inherently more stable. CAMP also rounded the heads more than most models, which makes them the easiest model to clean, which can be appreciated by anyone cleaning the pitch, especially a new climber.
The cables of this model are worth noting. They are slightly lower gauge than other options we tested, relative to their size, which has advantages and disadvantages. On the plus side, it's lighter and more flexible, so they are less likely to pull out due to rope drag while you are leading a pitch. The biggest downside is the cables are marginally more prone to kinking than other options, but not enough to take away from their overall performance. The other drawback is their size run; though this set includes seven commonly used sizes, it's not quite enough to be a stand-alone set. We think this run is great for alpine climbing or complementing other nuts you may already have on your rack, but may be lacking somewhat for an all-around trad rack on their own.
The Metolius Ultralight Curve Nut are among the lightest nuts we tested. The cables are embedded in the nut head, eliminating a swage and some cable, a technique mostly reserved for brass nuts. This makes these nuts lighter and less bulky, but it also makes their cables more prone to getting kinked. However, we aren't particularly worried because their cables are noticeably thicker (and thus more durable) than the typical brass nut.
The unique aspect of these climbing nuts is their double offset design. Their double-curved faces are great in irregular cracks and are extremely stable when placed since they always have three points of contact regardless of orientation. Unfortunately, they are also more prone to getting fixed and stuck, and they're just generally harder to clean, usually requiring a nut tool and some patience. If you are in the market for some light and versatile pieces to add to your rack, we think you should consider the Metolius Ultralight Curve Nut.
Two well-designed orientations add to their versatility
REASONS TO AVOID
Poor pin scar performance
Less useful in moderately tapered cracks
Walk easily
The Black Diamond Stopper is one of the oldest designs around. They are so ingrained in climbing history that many people refer to all climbing nuts as “stoppers”. Their time-tested design is very durable and easy to clean. You can easily slide the cable through the nut head, which is handy if you have to loop these over a bolt with a missing hanger. We like both of the orientations that this nut can be placed in, adding to its overall versatility.
That said, there is a reason why most other nut shapes have evolved so much; the basic design of the BD Stopper does not perform well in pin scars or irregular cracks. They work in parallel-sided cracks, but as today's climbers end up protecting any given pitch with mostly cams, they will benefit from a nut that works better in places where cams won't. They are easy to clean, but we also found rope drag causes them to walk and pop out more easily. We think you can buy better, more complementary nuts for the current cam-first generation.
Showing the Profile of a #11 Black Diamond Stopper
Credit: Ian Nicholson
How to Choose Climbing Nuts
This review focuses on climbing nuts used for protecting traditional free climbing routes as well as for aid and big wall routes. We tested all of the products in our review in a variety of rock types in places like Squamish, Eldorado Canyon, Yosemite Valley, the North Cascades, Smith Rocks, Red Rock, Joshua Tree, Zion, and more.
We tested all of the products in our review for over 100 days in over a dozen different climbing areas. We did this to compare how each model performed in a variety of rock types. Looking down for the top of pitch 6 of Ginger Cracks in Red Rock, NV.
Credit: Ian Nicholson
How They Work
The hold of climbing nuts works in slightly different ways, depending on the design and the nature of the crack. They are all, however, considered “passive protection.” This is because they don't press any force, use springs, or apply any mechanical advantage. They are simply set in a crack that constricts to a point smaller than the nut being placed, and (as long as the crack doesn't break), the nut can't fit through. This is different from spring-loaded camming devices, more commonly called cams, which are considered “active protection” because they actively expand into the crack they're placed in and use mechanical advantage to push out on the rock and stay in place.
In the most standard placement of a nut, the head is too big to fit through the crack below it. That is why all models have some taper and aren't just a square; instead, they're thinner on the bottom and broader on top. Different amounts of taper allow more or less surface area to contact the rock depending on the crack, which is the key to holding power. This is a foundational rule of passive protection - the more surface area in contact with the rock, the more secure the hold.
How a nut works is simple: simply slot into a crack where the head is too big to fit through the crack below it. This is why all models have some level of taper and aren't just a square. This helps to maximize surface area in a constricting crack, which is the key to holding power.
Credit: Andy Wellman
As a crack becomes more parallel or irregular, a curved nut design helps in two ways. First, the curve creates three points of contact (rather than two), which makes the nut more stable and, to a certain extent, allows the nut to cam into place. The second benefit of a curve is that it can potentially allow more surface contact with irregular and textured rock. All climbing nuts have a slightly different curve and taper, with each offering certain advantages and disadvantages. Of course, the magic is in figuring out what nut shape fits the greatest number of cracks that climbers want to use. The answer is complicated, but we'll go through it below.
Our review focuses on using climbing nuts used for protection for traditional free climbing routes as well as aid and big wall routes. Here, a string of nut placements on Desert Shield in Zion.
Credit: Graham Zimmerman
Nut Shape
Offset Taper
The offset taper is slowly becoming the most popular shape for general-purpose trad climbing. This is a change from years past, where curved nuts were the most popular. Offset models are best for flares and pin scars for which they are specifically designed. This is why offset models are becoming more popular, but it also has to do with cams. Small camming devices have made significant strides over the past decade and are now significantly better and more versatile than they once were. This means most climbers are more likely to carry and use far more cams than nuts on any given pitch.
An “offset” shaped head has become the new most popular shape as they fit in pin scars and small flares far better than a cam would. The “offset part” is instead of a more traditional nut that features a trapezoidal shape they are thinner on one side and wider on the other along two of their axes.
Credit: Ian Nicholson
It's this new cam-first generation of climbers that benefit the most from offset stoppers than in decades past. As most climbers are more likely to place cams anywhere they can, they are better off carrying nuts to fit where few cams will. This tends to be in flared cracks and pin scars where more traditionally shaped models and cams are mediocre but offset models are more appropriate tools.
While there are few “bad” designs, our testers prefer offset models for general purpose trad climbing. Because small cams have gotten so much better, most climbers place far more cams while offset nuts tend to work amazingly where cams just don't. Here Austin Hill sinks a nut on the second pitch of “Thin Air”, Smith Rocks, OR.
Credit: Ian Nicholson
Most offset climbing nuts, like the DMM Alloy Offset or the DMM Peenut, don't do as well in more parallel-sided cracks, but that's okay as most people are more likely to place a cam in these places anyway. Offset models are also generally harder to clean because they are asymmetric - they don't want to rotate upwards and instead more frequently have to be backed up.
This photo shows the classic “curved” design, where one of the two primary contact sides has a curve. This helps to accommodate more featured rock and helps maintain three points of contact to make the piece more stable.
Credit: Ian Nicholson
Curved Design
This is still the most common design used today, though offset models are gaining popularity. Their curve allows for three points of contact, giving greater stability to the piece while still letting it clean easily. The curve, which is generally only on one side, also helps the nut to bite even when placed in irregular or highly featured rock. An example of a curved model is the Black Diamond Stopper.
A photo showing a great example of how a curved nut accommodates more featured rock and doesn't need a perfect constriction in order to work effectively. While we slightly prefer offset models we still like more tradionally curved designs.
Credit: Ian Nicholson
Straight Taper
The straight taper has been nearly phased out, but there are still a handful of models with this design. For example, the Frost Works Sentinel Nuts feature a straight taper that was used on hundreds of first ascents throughout North America in the '60s and '70s and still holds well in a classic bottleneck. It is the most straightforward design for checking placement quality. The straight taper is not nearly as stable or versatile in flaring or parallel-sided cracks, though, and doesn't fit as well with irregular rock with sizeable crystals, as it doesn't have any clearance. While they are less versatile, they are still the easiest to clean.
Graham Zimmerman contending with several funky pods that can only be protected by offset nuts on the second pitch of “The Passenger”, Washington Pass, WA.
Credit: Ian Nicholson
Crack Types
Pin Scars
Pin scars result when pitons are hammered into the rock. These scars are common in climbing areas throughout North America, from Yosemite to Eldorado Canyon to White Horse and Cathedral Ledge. Smaller pin scars are places where traditional cams don't work very well nor do curved nuts. Offsets, however, are specifically designed for these scars and are frequently bomber in these locations where nothing else will even hold body weight. All the offset models we tested work pretty well in these types of cracks: the DMM Alloy Offset, the Black Diamond Offset Stopper, and for smaller spaces, the DMM Peenuts and DMM Brass Offset. They all fit perfectly in pods where other nuts are terrible.
Here is a classic example of a crack where offset models are bomber and a more traditional nut would be just mediocre. This is because the crack itself is subtly flared. Because of this, offset models will get more surface contact as they are tapered to fit these types of cracks.
Credit: Ian Nicholson
We love the DMM Peenuts. We appreciate that there's a little more mass to them and that they're easier to clean. However, for aid routes and big walls, it's hard to beat brass models. The DMM Brass Offset are made of brass, which is a softer metal than aluminum and thus deforms to the rock to give you better leverage and connection. This deformation means they aren't great for everyday trad climbing — but for scary, thinly protected trad leads and aid climbs where every little bit matters, they definitely offer a better bite.
With any nut, you want maximum contact with the head in order for the placement to be solid and be able to hold a fall. Here the nut is in a constriction which is good but the fact that only one half of one side of the head is in contact with the rock means the placement isn't particularly stable and more prone to popping out with rope drag.
Credit: Ian Nichlson
Parallel-Sided Cracks
Of note, all climbing nuts need some sort of crack constriction in order to function. We compared how different models perform in more parallel-sided cracks versus heavily tapered or flaring spaces.
All nuts need some sort of constriction in order to work. We just compared models in different situations and in this category compared how well different models worked in more more-parallel-sided cracks even if they still have some constriction.
Credit: Ian Nicholson
The Metolius Ultralight Curve Nuts is one of our top choices for parallel-sided crack performance. Their double curve design allows three points of contact pretty much no matter what, which makes them far more stable in these types of fissures. Other notable options include the CAMP Pro Nuts, which excel because of their high curvature along the side-to-side axis (the most common placement), helping the nut cam to remain more stable.
This photo is a good example of how classically curved models do better in more parallel-sided cracks by maintaining three points of contact. A CAMP Pro Nut is shown here.
Credit: Ian Nicholson
Most of the offset models didn't do as well in parallel cracks. The more parallel the cracks were, the worse they performed. They're not totally worthless in more parallel-sided cracks, but they're not as solid as curved models. Of note, the offset models are generally better in parallel-sided cracks than the curved nuts are in pin scars.
All pieces of protection need to strike a balance of being able to stay in the rock in the event of a fall, but also not be impossible for the second climber to remove. The role of the person putting the piece of protection in is certainly important but so is the design of the nut.
Credit: Matt Bento
Ease of Cleaning
Climbing nuts with more rounded edges or slightly more pronounced trapezoidal shapes are slightly easier to clean. However, it is challenging trying to give a single nut an “easiest to clean” designation.
During one of our side by side comparisons testing each nut's cleaning ability, Ian Nicholson puts his whole 175lb body weight on each nut before removing them.
Credit: Tino Villanueva
Overall we think the CAMP Pro Nuts and Black Diamond Stoppers are the easiest to clean of the traditional models. The Stoppers feature a nice trapezoidal shape, while the Pro Nut offers more curved edges. These are significantly quicker to clean than any of the aluminum offset models.
Balancing placing a nut that will hold you if you fall but isn't so challenging for your second to remove is an important skill of any trad climber.
Credit: Ian Nicholson
The Metolius Ultralight Curve Nuts are the hardest to clean. The two sides of curves on the Metolius, while conforming well to highly textured rock, tend to get hung up on small crystals and other deformities. It makes the nut super stable but also means it takes more skill to remove.
Most nuts are best backed out of cracks either by pushing on the wires or using a nut tool to “poke” it backward. You can yank the cable upwards but this is hard on the cables of all nuts particularly offset models which can kink after doing this repeatedly.
Credit: Ian Nicholson
Durability
The Black Diamond Stoppers are the most durable overall products in our review. While we don't feel there are any truly “flimsy” aluminum-headed models, they stand out for not getting too banged up during extended cleaning sessions.
Among aluminum nuts, we didn't find a giant difference in the durability of the heads, but there is a greater difference among their cables - certain models are more prone to kinking from aggressive cleaning.
Credit: Ian Nicholson
We also evaluated how easy it is to kink a cable during the use of any of the nuts we tested. In our experience, the Metolius Ultralight Curve Nut, DMM Alloy Offset, and Black Diamond Offset Stopper all struggle with this. With the three of these, the cables became kinked just below the head after too many upward jerks. Over time, this kinking caused the cable to unravel or exhibit a sharp bend just below the head, making them more challenging to place properly.
Brass models aren't as durable and thus aren't ideal for everyday trad climbing. However, for thinly protected free climbs, aid routes or big walls, they are pretty much mandatory and you just have to deal with the wear and tear. Here Rya O'Connell is thankful for a double set of brass offsets on the 5th pitch of Tangerine Trip. No camera tilt here, just look at the rope going straight down, STEEP!!!
Credit: Ian Nicholson
Most of the non-aluminum models we've tested are either brass or a copper-iron blend exhibiting similar overall characteristics. For example, the DMM HB Brass Offset proved noticeably less durable than aluminum options. Their brass heads are designed to deform to the rock for better “bite,” hopefully increasing the nut's holding power. However, this deformity is the biggest reason that we don't think brass nuts are great for everyday trad climbing. Sure, they work great — they just don't last super long. Most of the time, you could get away with using much more durable aluminum models. Still, for big walls, aid climbing, or sparsely protected free climbs, they are pretty much mandatory.
We think the classically curved models are fine but prefer offset models for all-around trad climbing. Here one tester sinks an offset on the first pitch of the Central Pillar of Frenzy, Yosemite, CA
Credit: Ian Nicholson
Nearly all of the models we tested can be placed in two orientations, adding to their versatility. However, the functionality of each model's secondary orientation varies significantly. Here a CAMP Pro Nut, one of the better performers in this metric, is placed along its secondary axis.
Credit: Ian Nicholson
Orientation Options
This refers to a nut's ability to be placed along both of its axes, a feature of all the climbing nuts we tested. All of the products we tested are best with the most narrow axis facing out and the wider axis contacting the rock. However, some models stand out for their versatility along both axes more than others.
Most models in our review featured some sort of trapezoidal shape. This creates two axis that the nut can be placed in. The more common placement is when the longer side is in contact with the rock. However it is still possible to place the nut with the shorter side in contact with the rock, but as there is less surface area touch this tended to be less stable and the differences between models were more pronounced.
Credit: Ian Nicholson
The Metolius Curve Nut, with its double-curved design, provides three points of contact on either side regardless of orientation and is the best. They are easy to read, leading us to place them in both orientations more often than others. Closely behind are the Black Diamond Stoppers, which are among the most stable in their secondary position.
Lots of nuts... Switching out pieces of passive protection for this review in Joshua Tree National Park.
Credit: Ian Nicholson
Nearly the same can be said for the DMM Alloy Offsets and BD Offset Stoppers. We applaud all of these models for their overall versatility and for being quite functional in either direction. Unfortunately, as much as we love the DMM Peenuts, they offer no real secondary options.
Different models accommodate more textured or larger grained crystals differently. Some manufacturers shaved part of the metal on their more dominate side to accommodate more textured rock which proves effective. Photo comparing the three best performing smaller-sized nuts in our review, from left to right: DMM Peenuts, BD Offset Micro, DMM Brass Offset.
Credit: Ian Nicholson
Different Nuts Excel at Different Rock Types
All of the nuts in our review work in all rock types. However, some excel in certain types of rock more than others. We love offset models for all areas, as they fit better where cams don't. But if you climb in an older area like Yosemite, Eldorado Canyon, Lumpy Ridge, or Cathedral Ledge (to name a few) that have plenty of pin scars, offset nuts are practically worth their weight in gold. They are perfectly tapered to fit old pin scars and are bomber, where a more traditional nut is just marginal and potentially not worth your time to try and place.
If you climb in an area with heavily featured rock like Smith Rock, Joshua Tree, or the Canadian Rockies, the CAMP Pro Nut or the Metolius Ultralight Curve Nut both stand out. These models excel in irregular and larger crystallized rock because of their more heavily curved shapes, which create more clearance to accommodate large crystals better than others, and they can maintain three points of contact even against textured rock.
Using a #2 Wild Country Rock on a Wire to show how the 3 points of contact design of curve nuts can excel in less constricting placements.
Credit: Ian Nicholson
Looking for a Complete Set
For climbers getting into traditional climbing, there are some critical factors. The size range is important. Having your nuts extend to over one and a quarter inches can be the right way to start on the cheap, using larger nuts to cover sizes some people might cover with cams.
Some models like the CAMP Pro Nut as seen here offer all the most commonly used sizes but are produced in the very smallest or largest ends of the spectrum meaning you likely have to couple them with another set. This is mostly for specific routes rather than everyday use.
Credit: Ian Nicholson
If money isn't an issue, we love the combination of the DMM Peenuts and the DMM Alloy Offsets. We think this passive protection size run will last most people through many stages of their climbing careers and work well for a wide range of users and rock types. We also think that people might not use the biggest model as often, nor the tiniest, but they are still useable, and we've already talked a lot about how valuable their offset design is.
With that said, for less money, we still really like the size, versatility, and durability of the Black Diamond Stoppers. These tried and true pieces offer two super useable axes with versatile and easy-to-clean shapes. They are sold in several different-sized sets, meaning you can start with a partial set and fill it in later, or buy the whole thing and double up on the most common sizes.
Tester Ian Nicholson performing bodyweight side-by-side comparisons on El Capitan, Yosemite, CA.
Credit: Ian Nicholson
Conclusion
Our team of experts, led by veteran climbing guide Ian Nicholson, takes testing climbing protection very seriously. Fun is also had, but resulting from the process is the most comprehensive review of today's most popular climbing nuts. When reading through our assessments, keep in mind the type of rock you want to climb, the style you like to climb, and other factors that are important to you to get the best set for your individual needs.
