1,Key Size:key holder accommodates up to 8 flat standard-sized house keys (max of 80mm long and 2mm thick each) and can be expanded to hold up to 14 keys using the included expansion kit. 2,It comes with a Loop Piece attachment for your larger car keys or car fob remote. 3, Material:Aluminum. 4,Perfect Organizer:it is also perfect for quick release keychain, bottle opener, pocket clip, multi tool, and many more.