Tcamp Aluminum Alloy Screw Lock Buckle Carabiners, Keychain Clip Hook Screw Lock Buckle, Hook Buckle for Outdoor Sporting Camping Hiking Hard aluminum alloy, extremely hard. Using D-type aluminum alloy polished, waterproof, wear-resistant, high strength, durable. You can hang on backpacks, key rings, kettle and everything you need to place, and can be used tents, ropes and other connection, stylish and practical. Not recommended as mountaineering, rock climbing, ice climbing and high-altitude games and other sports.