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DMM Belay Master 2 Review

A purpose-driven design that makes belaying safer and simpler.
DMM Belay Master 2
Top Pick Award
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Price:  $20 List | $14.96 at Backcountry
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Pros:  Gate keeper prevents cross loading, smooth screw action, ensures screwgate is locked
Cons:  Awkward to use, smaller gate opening
Manufacturer:   DMM
By Ryan Huetter ⋅ Review Editor  ⋅  Nov 16, 2016
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#5 of 11
  • Function - 30% 10
  • Ease of Unlocking and Locking - 25% 5
  • Compactness lightweight - 20% 6
  • Gate Clearance - 15% 8
  • Gate Hang Up - 10% 9

The Skinny

While it is possible to use most styles of locking carabiner paired with a belay or a rappel device in a pinch, certain styles perform much better at the task. HMS or pear-shaped lockers handle ropes moving around the basket of the carabiner better than small offset D shapes, especially when rappelling on double strands, and keep them from pinching and creating extra unwanted friction. A problem that can arise when using large locking carabiners appropriate to belaying is that the carabiner can become cross loaded between the device and the harness' belay loop, reducing its strength by up to two-thirds. Enter the belay specific locking carabiner design. There are a handful of these on the market now; the Belay Master 2 by DMM is among the most popular of these new designs intended to eliminate cross loading while belaying. To achieve this DMM has attached a removable plastic gate that swings shut and both locks the screwgate closed and captures the belay loop, keeping the carabiner from freely rotating. We also reviewed the Wild Country Ascent Lite Belay, another belay specific carabiner that uses a different means of preventing cross loading.

Read more about cross loading and the strength ratings of carabiners in our Buying Advice Article to see if a belay specific locker is right for your needs.

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Our Analysis and Test Results

Performance Comparison

The plastic gate keeper in action.
The plastic gate keeper in action.


Due to the fact that the Belay Master 2 is specifically designed for use with belay devices, we assessed it on its function in this use only. This is not the locking carabiner to be taken in the pack on a long overnight climbing trip into the mountains, on ski mountaineering trips or on most multi-pitch climbs. It is not intended for such uses, so would perform poorly if used for them. What it is meant for, is to keep the rope or belay device from becoming cross loaded against the belay loop, and it does a very good job at this. Less of an issue for top roping, where the slack in the rope is (hopefully) managed more attentively, the cross loading of the belay carabiner is more of a problem while belaying a lead climber.

More slack is inherently present in the system, and so the belay locker is allowed to more freely rotate if not attentively managed. We used the Belay Master 2 in conjunction with tube style belay devices like the Black Diamond ATC and Petzl Gri Gris while both lead and top rope belaying, and we found it to be intuitive and easy to use. When using the pivoting plastic gatekeeper, the screw gate must be locked for the plastic gate to close, serving as a reminder that the gate is locked. The spine of the Belay Master 2 is fluted slightly, which prevents the Gri Gri or similar device from binding along the spine, which is still a concern on other locking carabiners designed for eliminating cross loading like the Black Diamond Gridlock as well as the Wild Country Ascent Lite.

Another specific use for this style of locking carabiner is for use with a solo top rope belay device, such as the Petzl Micro Traxion. We climbed with the Belay Master while "mini-traxioning" on fixed lines and found it to be a better locker than others we had previously used. When rappelling, the likelihood of inadvertent cross loading is much lower, and the pivoting arm starts to be more of a hindrance than a help. We found in these instances the detachable gatekeeper was easier to just take off and stow away in our pocket until we reached the ground.

For single raps  the Belay Master 2 is a fine choice  but it is pretty awkward to load and unload double ropes when doing many rappels off a multi-pitch climb.
For single raps, the Belay Master 2 is a fine choice, but it is pretty awkward to load and unload double ropes when doing many rappels off a multi-pitch climb.

Ease of Locking and Unlocking

The Belay Master 2 is not the easiest locker to open and close, as there are more moving parts to secure the gate into place for use. Because the pivoting arm must open completely to unscrew the gate, it is much more cumbersome to leave the belay device and locker attached to the rope in between climbers as is often done in indoor or outdoor top roping sessions. The Wild Country Ascent Lite performed better at this aspect.

Other small locking carabiners like the Black Diamond Positron Screwgate work well as belay lockers for Gri Gri devices, and is much faster to open and closed. Some users, particularly those with larger hands, found it awkward to open the gate while the gate keeper was open, and were concerned about dropping it while high on the cliff. We agree, and would feel more vulnerable taking this carabiner on and off our belay loop on long routes.

The fact that the gate keeper can only be closed after the screwgate is fully locked gives us piece of mind. The screwgate can also not be opened until the plastic arm is removed, making it a more secure attachment than other standard screw gates.

The downside to this closure is that to stow the locker away on your harness without the plastic gate keeper at risk of popping off while climbing, the carabiner must be locked and unlocked each time, an annoying task if doing anything besides single pitch climbing.

The two belay specific lockers compared here: the Wild Country Ascent Lite Belay on the left  and the DMM Belay Master 2 on the right.
The two belay specific lockers compared here: the Wild Country Ascent Lite Belay on the left, and the DMM Belay Master 2 on the right.


The DMM Belay Master2 is the heaviest locking carabiner we reviewed, and when considering the plastic gate closure system, is also the bulkiest. That did not make too much of a difference to use considering that we were typically only using this carabiner when climbing in areas with pretty short approaches. The weight comes not only from the addition of the gatekeeper, but also from the heavier stock used. The Belay Master is hot forged and has I-beam construction along the crotch and spine, but the basket is a thicker, rounder stock with a soft angle leading into the spine, making for a durable and long lasting carabiner, something you want when using it as a belay carabiner.

The Belay Master keeps the device from rotating while belaying with a variety of devices.
The Belay Master keeps the device from rotating while belaying with a variety of devices.

Gate Clearance

The Belay Master 2 has adequate clearance to clip into assisted braking belay devices like the Petzl Gri Gri, as well as into tube style devices that require capturing one or two strands of rope as well as the keeper wire. Due to the plastic gatekeeper restricting where you can place your hand, the Belay Master 2 can feel easy to fumble when trying to clip large diameter gym ropes, and feels like it has a smaller useful clearance than it would seem at first glance. The Mad Rock Ultra-Tech HMS by comparison, had a similar sized gate opening but felt easier to clip because of its ergonomics.

The sharp curve gives the DMM Belay Master 2 slightly less gate clearance than we'd like to see on a larger locker.
The sharp curve gives the DMM Belay Master 2 slightly less gate clearance than we'd like to see on a larger locker.

Gate Hang Up

A keylock style nose is used on the Belay Master 2, which makes it a breeze to clip into the narrow attachment points on Gri Gris, and keeps skinny ropes from hooking onto the nose when clipping into traditional tube style belay devices.

It is a full-sized locker  though the plastic gate keeper makes it feel like a mini carabiner when opening it.
It is a full-sized locker, though the plastic gate keeper makes it feel like a mini carabiner when opening it.

Best Applications

Climbers looking for a locking carabiner that will allow them to avoid the dreaded cross loaded carabiner scenario (familiar to those who belay both leaders and top ropers alike) should look no further than the Belay Master 2. Our reviewers have climbed with most of these purpose-designed locking carabiners, of which there are quite a few, and feel like the Belay Master 2 is the best of this niche category. The added benefit of being able to remove the plastic gatekeeper clip, and to replace it at a nominal cost, puts the Belay Master 2 an extra step above its competition and for these reasons we give it the Top Pick Award for use with a belay/rappel device or for solo belay devices like the Silent Partner or Micro Traxion.

Set up to belay a single strand  something the Belay Master 2 excels at.
Set up to belay a single strand, something the Belay Master 2 excels at.


The DMM Belay Master 2, at $19.95, is one of the more expensive carabiners in the review, but considering its unique design and application, we feel that it is a good value for what you get. Other similar designs from other manufacturers are the same price, if not more, and with the Belay Master 2 you get the option of turning the carabiner into a more versatile locker if you remove the plastic gatekeeper, an option you don't have with any of the other belay specific lockers on the market.


This is a locking carabiner specifically designed for use with belay devices to keep them from cross loading against the belay loop, thus reducing their strength. In gym climbing and sport climbing applications, this carabiner could be a useful addition to your kit and could help improve your margin of safety. For climbers looking for a carabiner to use in a broader variety of situations, continue reading our Best Locking Carabiner Review to find something to suit you.

Ryan Huetter