BEARING STEEL CHAINSAW FILES: This chainsaw file is made of premium bearing steel, after elaborate production process, which features high hardness and durability, wear-resistant use, long life. HIGH HARDNESS CHAIN FILES: These round chainsaw files have sharp teeth, high hardness and strong wear resistance. Designed to sharpen all chain saw teeth, a great accessory for you. DURABLE CHAINSAW SHARPENER: Start filling by tightening chain tension to firmly support and file knives from inside to outside of knife. Quickly and easily remove dull and burred metal with the precise file design to prevent clogging. ROUND CHAIN FILE SHARPENER: These round chainsaw sharpening files have round shape, smooth cut and straight tang. Maintains the correct shape of the tooth and leaves an excellent cutting edge. FINE WORKMANSHIP CHAINSAW FILES: Low noise and simple appearance. These bearing steel chain saw files have sufficient anti-bending strength, wear resistance, high hardness, high wear resistance and high strength.