30 Diamond drill bits 40 grit coarse incredibly swift drilling shaping

Making jewelry working with glass wood metal stone, you need this set! 30pcs shapes, sizes, 40 grit (coarse). I use the cylindrical shaped tips for drilling beads. The flat top allows you to get the hole started without the bit traveling around (even on a curved surfaces). Once the hole is started and the bit is seated, switch to a diamond twist drill for faster drilling. The cone shaped tips are great for shaping stone settings. I keep all four grits handy for my work, (40, 150, 400, 600). Using these four grits, you can take most rough stone to pre- polish state.1/8 shank diameter for sanding, grinding, scratch and chip removal, pre-polishing preparation. These bits will fit in your Dremel, (use 1/8 collet), roto, moto, tools. Even works in a standard electric or hand drill with variable chuck. Great for drilling, shaping, grinding, stone, pearls, glass, metal, shells, plastic, wood, etc.Operate all rotary tools on slow speed only. Always use eye, lung, and hand protection! impeccable for everyday use. superior materials and excellent craftsmanship ensure long-lasting durability.