Subtle design features set this jig apart, including solidly constructed, black anodized precision machined aluminum jaws, stainless steel guide rods and an adjustment screw with a phosphor bronze bushing in a stainless steel roller bearing to reduce friction and maintain accuracy. Also, the blade/chisel is held tight to the guide rods by tightening the angled jaw faces against the tool edges. Guide holds bevel edge or standard bench chisels and plane irons from 1/4" to 2-3/4" wide. Use the included projection block to properly set your blade for the desired sharpening angle.