Round Shank Size: 3/32inch (2.35mm) round shank size, suitable for most rotary tools Material: High hardness, good toughness, high efficiency, fit for olive core, beads, ivory, wood, bone, precious soft metal some other micro-inlaid items Different Head Sizes: Each Pack has 6 different shape of the sculpture to give you more flexibility for your engraving. Extra small sleeve needle diameter 1.0MM, small sleeve needle diameter 1.4MM, medium sleeve needle diameter 1.8MM, large sleeve needle diameter 2.3MM, overall needle length 44MM Application: Widely applied to carving and grinding of various material such as metal, jewelry, wood, walnut and more; Highly recommended for olive core, beads, ivory, wood, bone, precious soft metal and some other micro-inlaid items Precision and Control: Engineered for smooth, accurate engraving, allowing for detailed designs and professional results in your crafting and DIY endeavors 24 Pcs 3/32inch (2.3mm) Round Shank Tungsten Steel Wood Carving Drill Bits for Rotary Tools, Compatible with Engraving Pen, Ideal for Precision Wood Olive Amber Engraving and Crafting 6 Different Cutter Shapes: ball,cone,peach,wheel,cylinder,umbrella Carving Head Size: 0.09 inch(2.3mm)/0.07 inch(1.8mm),0.05 inch(1.4mm),0.04 inch(1mm) Length: 1.73 in(44mm) Shank Size: 3/32inch (2.3mm) Application: widely applied to carving and grinding of various material such as metal, jewelry, wood, walnut and more; Highly recommended for olive core, beads, ivory, wood, bone, precious soft metal and some other micro-inlaid items Colour:As Shown Material:Metal Package Contents: 24 x Wood Carving 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 the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.