The blade tip is made with 4 edges, so it can be drilled closely to a real circle when compared to regular 2-edge drills, and the anchor insert is smoothly. The spiral has been given "marking grooves" for marking the depth of the holes. This drill is ideal for drilling holes made by Sanko Techno Co., Ltd. The blade is made to the 4 edge, reducing the burden on the worker. Blade pocket The use of this product allows for efficient discharge of cut particles stored in the hole for improved drilling work. Material: Concrete, block, mortar. Blade Diameter: 0.5 inches (12.7 mm). Effective Length: 6.3 inches (160 mm). Total Length: 11.0 inches (280 mm). Shank Diameter: 0.5 inches (13 mm). Compatible Models: Hammer Drill. Shank: -Hex Shank: Hex shaft.