The Lansky Controlled Angle Sharpening system is designed to give your knife a razor-sharp edge every time you use it. The patented Lansky system makes it easy to sharpen with a constant angle which gives you an optimal result. You fixate the knife in the clamp and then keep a constant angle during sharpening thanks to the guidance system. The Controlled Angle system includes sharpening wheels made of aluminum-oxide and ceramics.