Premium sub-micron grade solid carbide, Made in USA Easily resharpens chainsaw teeth in seconds Compatible with Timberline Chainsaw Sharpener "Sharpener for Stihl Brand" 3/8″ Pitch Chain C2 sub-micron grade solid carbide cutter. 92 Rockwell hardness. Built to last for years of normal use and multiple sharpenings to keep you chainsaw cutting like new. Works with namebrand Timberline jig as well as off brand jigs of similar design.