Paracord Planet's Locking Aluminum Carabiners used a high-quality spring-loaded gate with a screw lock. This allows them to be quickly and securely attached to fixed points. It can be used for a hiking, camping, paracord, fishing, backpacks, keyring and many other things. Not suitable for climbing, swinging, hammocks or similar activities. The Locking Aluminum Carabiners are made of a lightweight, durable aluminum material which makes it practical and strong.