Ingersoll Rand 285B-TK1 is a multi piece tune up kit that includes a slot cover, plunger for the throttle valve, throttle valve, spring for the throttle valve, O-Ring, stop pin, spring, ball, reverse valve seal, pin spring, gasket for handle, rear rotor bearing, vane pack (set of 6), front rotor bearing, O-ring, retainer ring, hammer case gasket and oil seal.