Rider double sided diamond stone 400/1000

These 200 x 65mm double sided premium quality diamond stones provide two options, just by flipping them over. We tested these extensively, and they feature medium 400 Grit (36 micron) on one side and fine 1,000 Grit (15 micron) on the other. Nickel plating permanently fixes the diamond particles onto the 8mm thick steel base. A chequered pattern carries away metal particles, thereby maintaining the stone's cutting efficiency. The resulting surface is more than capable of sharpening modern hard steels, ceramic knives as well as traditional tool steels. A protective non-slip rubber surround keeps the stone in place when in use. You can use it when dry, but it works far better with a splash of water.