This blade is a direct replacement for the one included with your Bench Dog® Tools 3-in-1 Shoulder Plane (#52378, sold separately). Having a spare iron on hand ensures youll always have a sharp edge to deal with challenging grain, and you can also purchase multiple blades and grind each to a different bevel angle to suit a range of applications. The blade is made from 1/8 thick hardened carbon steel for reduced chatter and excellent planing characteristics. Features: Fits the Bench Dog 3-in-1 Shoulder Plane (#52378, sold separately)1/8 thick carbon steel for chatter-free performanceMay require honing