Features: brand new and high quality ● This product is mainly made of 45# steel/40Cr steel, and the YG8C bit is welded by hard alloy. Based on high-quality for raw materials, after high temperature quenching, the hardness is greatly improved, and it is longer than ordinary medium carbon steel drill bits. ● The surface of the copper for cross for head, self-centering tool tip, high-speed drilling, fast chip removal; four-groove design, fast chip removal, reducing wear. ● Used in conjunction with an electric hammer, it is used for drilling glue, concrete, brick walls and other stones. It is widely used in construction, installation and other industries. It is an efficient professional drill bit. ● Specification: (5/6/7/8/10/12/14x110mm) ● Quantity: 7-piece set Specifications: Material:Cemented Carbide Color ：Silver Size1: Approx.5x110mm/0.19x4.33inch Size2: Approx.6x110mm/0.23x4.33inch Size3: Approx.7x110mm/0.27x4.33inch Size4: Approx.8x110mm/0.31x4.33inch Size5: Approx.12x110mm/0.47x4.33inch Size6: Approx.14x110mm/0.55x4.33inch Package Includes: 7PcsxRound Shank for Cross Drill note: 1.Please allow 1-2mm errors due to manual measurement, make sure that you do not mind before you order. 2.Due to the difference between different monitors, the picture may not reflect the actual color of the item.