Triple action auto-locking HMS carabiner 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.Features:Belay, Rappel, RiggingAutomatic lock requires three actions (slide, twist, and pull) to openEasy to operate with one handLarge opening and keylock nose make clipping ropes and webbing easy