The body of this plane is ribbed to ensure strength and rigidity. The machined faces of the frog bed sit firmly onto similar machined faces on the body of the plane and then fastened in position by two screws. This positive positioning helps prevent chattering. The cut iron is made of high carbon steel, hardened and tempered under scientific control for accuracy and uniformity. Handle and knob are hardwood. This #5 plane is referred to as a “Jack” plane because it can be used in so many ways that it is a jack of all trades. Not small, not large, just the perfect size for multiple task