Precise & Long-Lasting Sharpness: Any serious chef knows quality knives are expensive. Keep yours cutting like new for much, much longer with a Tumbler rolling knife sharpener.Powered by Diamonds: The knife sharpening kit is plated with nature's hardest, most-effective sharpening stones: diamonds. The D35 grit size effortlessly restores sharpness to your knife's edge.A Finer Edge: A proprietary stainless steel helix disc on the other end of the kitchen knife sharpener removes the burr of your knife’s edge after the base sharpening.Simple, But Effective: Simply choose your angle and use the magnetic knife holder to secure your blade. Then, roll the sharpening disc back and forth until sharp.15 & 20 Degree Angle Sharpening: Easily & quickly sharpen traditional and specialty blades.