The Eze-Lap diamond chainsaw chain sharpener is a 3/16" diamond coated grinding attachment with a precision guide for exact control over the depth and angle of cut. It is compatible with all cordless or 240v drills operating at 200-5000 RPM, and is suitable for sharpening all types of steel or tungsten carbide tipped chainsaw chains without risking the cutting edge overheating. Crafted in the USA.