The Porter-Cable 43082PC is a 3/8 inch Rabbeting Bit. The Porter-Cable Professional Edge router bit is constructed of 4140 Alloy Steel, a harder grade of steel than standard cast steel bit bodies. Each bit is annealed and heat treated to Rockwell hardness of 40-45 harder than is possible with cast steel bodies. A black oxide coating protects against corrosion while preventing resin build up and improving chip clearance. The bit cuts a 3/8 inch rabbet on the edges of wood, plastics and solid surface materials.