1.Excellent Design: This chisel is perfect for squaring up the corners of routed mortises. It has a hollow core design with the cutting edge on the inside of the 90 degree. The cutters are 12 mm and 1/2'8mm. It sports a ribbed rubber handle that fits the hand well. It has a solid striking head. Solidly built and perfect for getting those clean, sharp corners on door installations and framing. 2.Easy to use: This corner chisel is made of a comfortable ribbed rubber handle and a sturdy metal knockout cap. Just use a hammer to gently knock to quickly chisel out square corners. 3.Strong & Sharp Blade : Our square mortise chisel is made of high hardness steel. The blade is strong and sharp, not easy to deform. It can easily cut different materials of wood. 4.Wide Applications: This corner chisel tool is perfect for hinge recesses, door hangings, door strike plate, framing, cabinet making, picture frames and many other applications that require 90 degree angles.