Process: high frequency quenching and hardening treatment.This tool for chamfering is suitable for stainless steel with or without thread, hardened steel, mild steel, copper, brass, aluminum, fiberglass, wood, plastic.The operation is simple, using lowest speed on drill bit, and then slightly applying pressure to remove burr.Removing burrs does not hurt hands and improve efficiency.It is suitable for all kinds of chuck drill and meet different needs.Name:External chamferer, chuck electric drill chamfering toolColour:A:SilverMaterial:MetalPackage Contents:3 * hexagonal Handle ChamferOnly above package content, other products are not included.Note: Light reflection and different displays may cause color of item in picture a little different from real thing. The measurement allowed error is +/- 1-3cm.