The Dorman 12mm Outlet Heavy Duty Clutch Servo is a precision machined and constructed replacement part designed to restore the pneumatic pressure required to reduce the stress necessary to activate the clutch pedal. Made with quality materials for a reliable lifespan, this direct replacement servomotor is designed to match the fit and function of the original part on 2013-2021 Kenworth and 2013-2021 Peterbilt vehicles. FleetPride is your First Click in Heavy Duty®.