File, which is made of carbon tool steel T12 or T13 after heat treatment and then quenching of the working part, is a small production tool. It is a hand tool used to sharpen the saw chain's cutters.
| Size | Application |
| 4.0mm | 12'/14'/16' chain saw |
| 4.8mm | 16'/18'/20' chain saw |
| 5.5mm | 3/8" .404" saw chain |