Replaces thermostatic actuator element in the Jagg 4700 offset oil filter adapter with new Viscosity Regulated Flow (VRF) actuator Converts a Jagg #4700 offset oil filter adapter into a Jagg #4701 offset oil filter adapter with Viscosity Regulated Flow After filtration, the oil may either travel to the oil cooler or by-pass the oil cooler, according to the built-in Viscosity Regulated Flow (VRF) plug function Cold, viscous oil will by-pass the oil cooler, speeding warmup to standard operating temperature As the engine reaches operating temperature and oil reaches optimal viscosity range, the VRF plug will keep the #4701Æs by-pass hole closed, sending hot, filtered oil to the oil cooler, and delivering cool, clean oil to the engine Includes viscosity regulated flow plug, spring, button head with O-ring, AFM gasket, large O-ring. PLUG VISC REG FLOW