This 12V 500A starter relay is compatible with part numbers C10013, C10014, C10018, 10020, 10024, 12053, 12503, 13501, 14061, 14501, 14551, 14552, and 40252.Constructed with copper, EPDM, and metal materials, it is designed to handle cranking power and reduce startup switch current.Terminal B is for connection and terminal M is for motor connection; reverse connection is not recommended.Suitable for 12V systems in motorcycles, ATVs, and UTVs.Package includes one starter relay.