1mm 20 pcs. 2mm 20 pcs. 3mm 20 pcs. Diamond Drill Bits - 1/8" shank Suitable for use with hand drills, flex shafts, and Dremel tools Ideal for jewelry making: necklaces, earrings, pendants, bracelets using sea shells, beach glass, rocks Drill clean holes in tiles, marble, rocks, ceramic, porcelain, gemstones Requires practice; breakage may occur during learning process Use with water cooling only—do not run dry Total length: 1.77 inches Packaged in a plastic storage box for easy carrying and organization Can drill beach sea glass, sea shells, rocks, marbles, and similar materials Color: silver Material: diamond coated Size: 1mm, 2mm, 3mm Package includes: 2 sets * 30 diamond grinding needles Wet drilling required—these are delicate, small-diameter bits with thin diamond coating; avoid excessive pressure or impact Start drilling at an angle; gently move the bit to enlarge the hole gradually; allow the tool to work without forcing Packaging includes only the items listed above; other accessories not included Note: Lighting and display settings may cause slight color variations between image and actual item. Measurement tolerance: +/- 1-3 cm