They work with almost any brand of mil-spec 1911. KimPro Tac-Mags feature an exclusive quick change floorplate that allows the immediate attachment of any one of three included bases - stainless steel, slim bumper pad for carry or thick bumper pad for competition or use with extended magazine wells. Built for exceptional performance, they have all stainless steel construction and a Teflon coated stainless steel follower. Rocket Wire springs give 25% greater endurance limits than conventional springs, and large numbered round recognition holes read at a glance.