Provide exact torque measurement when making up pump parts Three piece precision machined jaws grip specific O.D. by friction and do not mar the surface of parts Ratcheting ability prevents frequent tong adjustment or removal Can be used with any 1/2″, 3/4″ or 1″ drive “click-type” torque wrench handle Note: Wrench head, adaptor and torque wrench handle must be ordered separately.