This cam clamp has an 8" opening and 8-1/2" depth. Cam clamps are widely used by furniture restorers, cabinetmakers, luthiers, and hobbyists. Light in weight with a quick cam action that produces 330 lbs. of pressure when fully cocked. The bar is made of spring steel. The jaws are made of lacquered maple with a cork face to prevent marring and staining the workpiece.