High Quality Diamond Drill Bits 4 different sizes - 1mm, 1.5mm, 2mm, 2.5mm 10pcs each Suitable for drills, flexibles and milling cutters. Creators drilled holes in sea glass, shells, rocks, marbles, stones, etc. on the beach. Make your own earrings, pendants and bracelets. Color: Silver Material: Emery Package Contents: 40 x Diamond Drill Bits Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in a little different from the real thing. The measurement allowed error is +/- 1-3 cm.