Dry Drill Core Bits for Brick, Concrete Block, Masonry - 6" Diameter 5/8"-11 Threaded #30/40 Diamond Grit #30/40 diamond grit for drilling soft brick, soft masonry, concrete block Diameter: 6 inches Thread: 5/8"-11 threaded Drilling depth: 9.5" High diamond concentration and quality guarantee longer coring life, solid poured concrete Not commended