Stanley 1-3/8 in. Block Blade for 6-1/4 in. Low Angle Block Plane is designed specifically for the Model 12-960 6-1/4 Inch low angle block plane. Crafted from hardened, tempered high-carbon chrome steel, this blade excellent edge retention and durability. It can be honed to a razor-sharp edge, ensuring precision and smooth performance. The blade is ground to a flat surface, making sharpening easy and efficient. It comes with an accurately ground edge of 25°, and it is to finish with an additional honed angle of 30° for optimal results. Model Number: 12-504