10 different pieces of stone grain 80, 120, 200, 400, 500, 600, 800, 1000, 1500, 2000 GRAIN. The diamond stone is smooth, it uses a single crystal diamond, to wear, long lasting. When polishing, choose 1000 1500 2000 grain if you grinding, 600-800 grain if you make coarse grinding, 80-500 grain. size:16*2.4 Cm Material:Diamond colour:black Package Contents: 10 * Whetstone Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm. The diamond stone is smooth, it uses a single crystal diamond, to wear, long lasting. When polishing, choose 1000 1500 2000 grain if you grinding, 600-800 grain if you make coarse grinding, 80-500 grain. 10 different pieces of stone grain 80, 120, 200, 400, 500, 600, 800, 1000, 1500, 2000 GRAIN.