CAMP HMS 3 Lock
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The C.A.M.P. HMS 3 Lock Carabiner is a Triple action auto-locking HMS carabiner that requires three actions to open the gate making it safer than standard twist lock carabiners, which require two actions to open. This is the best choice when using an auto-locking carabiner to belay.
With three actions to open it, the Camp USA HMS 3Lock Carabiner is one of the safest choices for climbing, whether you're belaying or rappelling. Slide the locker up, twist it clockwise, and pull it open. The keylock nose eliminates snagging your rope.