This item is Bosch HCBG12 Blue Granite Hammer Drill Bit Carbide Tip 3/8 x 4 x 6 inch, used for power tool accessories, drill bits and accessories; the product is manufactured in China, milled U-shaped flute and deep cut spiral designs, Diamond Ground Carbide Tip; perfect on centre diamond tip grinding for fast starts and drilling; ideal for concrete, brick and masonry