Description:Made of fine quality material, low resistance, high hardness, improving work efficiency.The design of triangle shank makes the clamping more tight and does not slip.U-shaped spiral is smooth and flat, and the drilling is smoother.Strong toughness and wear resistance, can be installed in electric drills.Provides smooth and accurate drilling in tile, brick wall, wood and so on.Total length:3mm cutting diameter: 80mm / 3.1in4mm cutting diameter: 80mm / 3.1in5mm cutting diameter: 80mm / 3.1in6mm cutting diameter: 100mm / 3.9in8mm cutting diameter: 110mm / 4.3in10mm cutting diameter: 120mm / 4.7in12mm cutting diameter: 120mm / 4.7inFeatures:Type: Drill BitMaterial: Hard AlloyQuantity: 7Pcs/PackTool Holder Type: Triangle HandleCooling Type: Outer ColdBlade Top Corner: 135°Category: Hole expansion drillSize: 3mm, 4mm, 5mm,6mm, 8mm,10mm,12mmWeight: Approx. 150gPackage includes:1 x 7Pcs Set (3 4 5 6 8 10 12mm)