10pcs carbide mini drill 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 1.0, 1.1, 1.2mm Stem diameter: . 1/8 inch (3.175 mm) , it can drill 2000-5000 pcs in normal working conditions, can also go back grinding 4-5 Materials: alloy and high quality Drilling has a area of leftover discharge, little resistance and softness when dumping waste. Using high quality materials and proper grinding process makes sharp bit , reduce cutting force and breakage drilling, the quality of the wall of the hole. The cutting edges avoid strictly partial hole, the quality. Package Contents: 10 x drill Only the above package content, other products are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.