The Trium Diamond Cams Pro knife sharpener double from de Buyer lets you easily restore your worn knives to their original pristine condition. The sharpener features two different compartments: the first can be used to sharpen very worn and dull knives. The second compartment, though, has two functions — a deeper notch can be reached on this side by pushing the knife further down into the slit and pulling the blade in a sweeping arc. A shallower notch in the same compartment can be used for general maintenance — ideal if you want to sharpen your knives daily to keep them at top quality!