Blade G30C Solid Carbide Triangular Blade (G30C). G30C Carbide Blade - 3 Cutting corners. Cleans corners and removes radii after machining for a smooth flush finish (G30C). Works with blade holder "G3" . Great for Inner Straight Corners. Good for use on Steel, Aluminum, Copper, Brass, Cast Iron, Stainless Steel, Hardened Steel and Plastics