Carabiner
A forged metal link, made of either aluminum or steel, with a spring-loaded gate that can be attached by a climber to a piece of gear like a cam or a bolt for climbing protection as well as to anchor the climber to a belay ledge. Carabiners are a common and basic piece of climbing safety equipment that are used in most climbing activities, including climbing, belaying, and rappelling. They come in two basic shapes—oval and D-shaped—as well as with non-locking gates and locking gates that can be locked shut by screwing a sleeve or an auto-lock gate. The three types of gates on non-locking carabiners are straight, bent, and wire. Sometimes called a biner or a crab. The original German word Karabinerhaken means “hook for a carbine rifle.”
Petzl Spirit Carabiner with a bent gate.
