Ideal for occasional chain saw users, this durable and economical tool makes hand sharpening easy. Includes both a 12-volt car adapter and battery clips for convenient use anywhere. Simple sharpening angle adjustment guide for accuracy. Sharpens any round-ground 1/4-in, 3/8-in Low Profile, .325-in, 3/8-in or .404-in chain. High impact housing holds a powerful motor that runs at an optimum 25,000 rpm. Shank lock feature allows easier stone replacement