Feedback Sports Pro Mechanic Clamp. The patented ratchet-action closure and speed release clamp of the Pro Mechanic repair stand is capable of managing any bike frame up to 75lbs (34kg) and tube diameter up to 2.6 (6.6cm). This replacement clamp head comes fully assembled with hinge pin and hinge pin fixing bolt. Includes entire clamp head assembly hinge pin fixing bolt clutch body clutch cups and rear tri knob.