However, there is no need to discard blunt knives, if you use this sharpening steel. All good kitchens need a sharpening steel, like the Zwilling Twin 1731 model, as it restores sharpness to blunt knives in seconds. 23cm in length, the sharpening steel is also suitable for use with large knives, like chef's knives or slicing knives.The sharpening steel is simple to use: simply draw the sharpening steel several times along the cutting edge of the knife and then immediately enjoy the ultra-sharp results. This model also has a tungsten carbide sheath to provide for easy and quick sharpening. This material is a little rougher and can be compared to fine sandpaper. It grinds the blade and restores the knife's cutting properties.The sharpening steel per se is also extremely durable. This sharpening utensil from Zwilling is the perfect choice for anyone who wishes to enjoy sharp knives when cooking.Tungsten carbide is a hard metal with ceramic constituents.