Check the listing for details. Second Cut Grade High Carbon Steel Triangle Side Three Square File 6 Inch. Condition: New. Listed at 17.18 USD. Description:High Carbon Steel Ensures Longevity and Strength.Second-cut grade is for deburring, shaping, and sharpening.Round side with double-cut teeth puts a smooth finish on interior contours and holes.Flat side with cross-cut teeth removes material quickly for fast rough-shaping of larger surfaces and edges.Precision Milled, Tempered and Coated Teeth provide durable cutting and good performance.Do not try to file hardened steel with a hardened steel file; you will quickly ruin the file. Also diamond-embedded files should not be used on soft materials, including many soft steels, as this will cause the diamonds to be torn out. Clean out any bits of file metal with a stiff wire brush. Chalk/oil the file: rub a small amount or oil into the teeth of the file to:1.