i have used those 5MM Mini Caribiner and they are kinda weak, i have used to use one to atach my keychain to my trouwsers, but the spring lost his strengh after a wille and i destroyed the spring somehow after a while. the closhing part end up daggeling from the joint.... so i would recoment a stronger ( aluminium/steel ) carabiner even for light duty work..<br>i peorsonally use aluminium carabiners even for my keychain and other stuff....