Alloy head material with stronger hardness. When drilling hard materials (glass, porcelain tile, marble or ), please use for lubrication. Triangular handle design, more stable operation. U-shaped slot type, conducive to chip removal, no damage to the tile wall. Ordinary impact drill, drill can be installed on the use, easy to carry decoration Color: silver black Material: Carbide Dimensions: blade diameter 3mm 4mm 5mm 6mm 8mm Package Contents: 20 pcs * drill bit Only the above package content, other products are not included. Note: Light shooting 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 +/- 1-3 cm.