40pcs 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: approx. 1/8 inch (3.175 mm) Long life, it can drill 2000-5000 pcs in normal working conditions, can also go back grinding 4-5 times Materials: alloy and high quality Drilling has a large area of leftover discharge, little resistance and softness when dumping waste. Using high quality materials and proper grinding process makes sharp bit sharper, reduce cutting force and breakage drilling, improve the quality of the wall of the hole. The cutting edges avoid strictly partial hole, guarantee the quality. Package Contents: 40 x drill 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.