American pattern round chainsaw file. Round shape, smooth cut, straight tang. Tighten tension on chain to firmly support cutters when filing. File from inside to outside of cutter. Place file against bevelled cutting surface of teeth 20° to 45° with saw. Follow saw manufacturers" specifications. Sharpen all left hand cutters on one side of chain. Then move to the other side and file all the right hand cutters. Check depth gauge height every 2 or 3 sharpenings. Height between cutting teeth and depth gauge is between .020" to .030". 6" Length.