This heavy duty self-tightening grip with a capacity of 1200 lb (5.3 kN) is ideal for a range of tensile testing requirements. The serrated steel jaws are easily opened with an ergonomic spring loaded knob and rack and pinion type mechanism. The jaws ride on rollers instead of sliding along the surface of the housing, as with conventional wedge grips. This unique design prevents jamming and improves gripping characteristics.