The Trend CRDWSCCFC is a double-sided credit card size diamond stone It has monocrystalline diamonds for fast clean stock removal and excellent sharpening performance Double sided for coarse sharpening and fine honing Coarse 360 grit nom 40 microns and fine 600 grit nom 25 microns Ideal for fluted shaped and small router bits carbide or HSS turning tools chisels plane blades carving tools and all general tooling Recommended for use with Trend lapping fluid to prevent clogging or rusting and assist in keeping tools clean