Nicholson 4 in. L X 0.25 in. W High Carbon Steel Bastard Cut File 1 pc, Pack of 12

The Crescent Nicholson single-cut bastard mill files sharpen mill or circular saws and are ideal for draw filing and finishing metals. The rectangular shape lets you smooth and sharpen straight surfaces. 2 square edges allow you to make grooves fixed at the same width as the file, and all sizes taper slightly in width to improve access in slots.