In an average sharpening time of 10 seconds, it will put a razor edge on knives and many other types of cutting tools. Pre-set sharpening angle to provide the keenest edge every time. Diamond honed tungsten carbide sharpening blades for an excellent sharpening finish. Reversible blades have an expected life of 4 to 5 years. Durable ABS plastic handle and tough finger guard for safety.