The Stanley hand tools surform half-round replacement file blade is great for faster stock removal and shaping curved surfaces and ideal for work on fiberglass and removing filler for cars and boats. Half round convex blade for faster stock removal and shaping curved surfacesIdeal for work on fiberglass and removing filler for cars and boatsRound, regular cut, fits #21-099 (do not stock), 21-295 (2511-8449), and 21-296 (2511-8415)10 in. overall length