Industrial-duty clutch mated to high-performance Cat Pump increases durability and dependability. Convenient remote control of on-off function optimizes system performance. Superior strength forged rotor, hub and armature offer superior flux and maximum torque for long life. Double groove 12.4" pulley, "B" type belt and 24mm shaft. Fits Cat Pumps 530,550,56,57,70 & 781 plunger models.