This is a BRAKE Assembly from a 1/3 HP MOTOR from a RAYNOR Jack Shaft Operator model RBJ 511 SR2 overhead door opener It is used,from a take-out during a remodel upgrade to a larger door. It has been TESTED and checked for wear, and is in perfect condition It will fit other makes and models. This assembly is a motor brake only is complete with the hub and shaft pulley. ALL Parts will be packed accordingly to be protected in normal shipping. . RETURNS: Sorry there are no returns on ELECTRICAL PARTS stk#(743)A24