BLACK DIAMOND RockLock Screwgate Locking Belay/Rappelling Carabiner, Black Review (2026)

What the RockLock is built for

The RockLock is a pear shaped, HMS style locking carabiner from Black Diamond built specifically for belaying and rappelling rather than as a general purpose rack carabiner, and Black Diamond describes it as their largest locking carabiner for that reason. The pear shape, wider at the top than a standard D shaped locker, gives extra room for a belay device, a GRIGRI, or a Munter hitch to move freely without binding against the carabiner's spine, which matters most at a busy belay station or anchor where a climber is managing rope through the device repeatedly. It uses a manual screwgate sleeve rather than an auto locking mechanism, which is simple to operate and easy to visually confirm as locked.

Strength and weight specs

Black Diamond's published specifications list a closed gate strength of 24 kilonewtons, an open gate strength of 7 kilonewtons and a minor axis strength also around 7 kilonewtons, all comfortably above the minimum strength requirements for a climbing locking carabiner. It has a 21 millimeter gate opening and weighs about 85 grams, and the nose is a keylock design, meaning it has no notch for a rope, sling or bolt hanger to snag on when clipping or unclipping under load. These numbers put it solidly in the category of a robust, general belay and rappel carabiner rather than an ultralight rack biner.

Using it at the belay

In everyday use, climbers clip the RockLock to their belay loop for a GRIGRI or tube style device, or use it at an anchor for a Munter hitch when a mechanical device is not available, and the pear shape's extra room makes both of those tasks noticeably easier than with a narrower carabiner. Because it is a manual screwgate, the standard habit of checking that the sleeve is fully screwed down before weighting the system applies here, since a screwgate can work loose over a long belay session if not checked periodically, unlike an auto locking design that locks itself after each use. The keylock nose also helps it glide smoothly onto bolt hangers and other carabiners without snagging during anchor building.

How it compares with other lockers

Against Petzl's William, another large pear shaped screw-lock carabiner built for the same belay station role, the two are close competitors, with the William rated slightly higher on major axis strength at 27 kilonewtons versus the RockLock's 24, though both comfortably exceed real world climbing loads. EDELRID's HMS Strike, a triple lock carabiner, adds an extra automatic locking stage for climbers who want more security than a manual screwgate at the cost of a slightly more involved unlocking motion. The choice between these pear shaped lockers usually comes down to gate feel, nose shape and brand preference rather than a meaningful strength difference, since all are built well above minimum climbing standards.

Who should buy it

The RockLock suits climbers who want a dedicated, roomy locking carabiner for their belay device or GRIGRI, and anyone who regularly builds anchors using a Munter hitch and wants the extra clearance a pear shape provides. It is a solid pick for a first dedicated belay carabiner or as a backup for building multi pitch anchors. Climbers looking for the lightest possible locker to save weight on a long alpine route, or who prefer an auto locking mechanism over a manual screwgate, should compare it against lighter wiregate lockers or triple lock designs like EDELRID's HMS Strike.

Frequently asked questions