Aiskaer 60 Pcs Premium Diamond Drill Bit Cylindrical Burr Kit Jewelry Beach Sea Glass Shells Gemstones Lapidary.1mm 20pcs.2mm 20pcs.3mm 20pcs 1mm 20pcs. 2mm 20 pcs. 3mm 20pcs.Diamond Drill Bits - 1/8 shank Practical - Suitable to be used with hand drills, flex shafts and dremels. Perfect Jewelry Design Necklaces Earrings, Pendants, Bracelets with Sea Shells, Beach Glass, Rocks Make Clean Holes in Tiles, Marble, Rocks, Ceramic, Porcelain, Gemstones Experience needed, you may break few bits during practice. Use with water - do not run dry.