Material: \r\nABS + Stainless steel slot\r\n 4 stage slot material: Ceramic + Tungsten steel + Diamond\r\n\r\n\r\n Fast work: \r\nThis knife sharpener works great on most types of knives. Keep your knives sharp and ready to use. It is very easy to use, and very sturdy and durable.\r\n\r\n\r\nHow to use\r\nPlease place the knife sharpener on a stable surface when using.\r\n Complete one or both of the following steps depending on how blunt the blade is.\r\n\r\nSlot 1: \r\nOpen the scissor and hold the handles tightly, then put the scissor blades into the slot. Using suitable manpower to clamp the Emery roll, finally slide the scissor backward for some times.\r\n\r\nSlot 2: \r\n Use this only if your knife is very blunt, using the slight downward pressure, run the blade from its heel to its point through the slot. (One direction only, do not move backward and forward.) Repeat three times, once every six months or as required.\r\n\r\nSlot 3: \r\n Always finish off with this step to remove any burrs that result from the re-edging and rough honing process.\r\n Without using pressure, run the blade through the ceramic rods five times backward then forward from its heel to its point.\r\n You can also use this step on its own to maintain a sharp blade.\r\n It’s recommended to do it approximately once a week.\r\n\r\nSlot 4\r\n Hold sharpener on sturdy surface. Lightly pull knife through slot, from heel to the point, move in one direction only.\r\n Repeat two or three times or until sharpened.\r\n\r\n\r\n\r\nCaution: \r\n 1.Do not use the knife sharpener to sharpen serrated blades.\r\n 2.To avoid damaging the knife, please sharpen the knife lightly and don’t sharpen back and forth.\r\n 3.The ceramic rods may discolor after use, this is normal.\r\n 4.Do not put the sharpener in the dishwasher or submerge in water.\r\n 5.Please put the knife sharpener and knife beyond the reach of children to avoid any accidents.