The Sabatier Professional Two Stage Knife Sharpener features a ceramic tool for regular honing and a tungsten carbide tool for resharpening a blunt knife. Fine honing stage (white ceramic rods): Use this slot to keep an edge on a sharp knife. Regularly draw the blade through from heel to tip holding it vertically and your edge should stay well honed. Re-edging stage: When your knives has become blunt you will need to recut the edge using the tungsten carbide stage. Draw the knife blade through two or three times form heel to tip keeping it vertical at all times. Finish the edge with a few strokes through the honing stage.