Used for backpacks, key rings, kettle etc 100% brand new and high quality Outer diameter: Approx. 2.5cm Inner diameter: Approx. 1.7cm Can also used to connect tent and rope Not suitable for mountain climbing, rock climbing with a heavy load Material: Aluminum Alloy Durable material, nice design Package Included:5x Carabiner note:1.Please allow 1-3mm error due to manual measurement. pls make sure you do not mind before you bid.        2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.