1 3/8" in Diamond Core Drill Bit X 6" Long 35mm x 152mm 5/8-11 Thread For Core Bit Adaptors Or Angle Grinder Cut Concrete Brick Cement Block Masonry Products fits any of our 5/8-11 UNC Core Bit Arbors. These concrete Drill bits have diamond mixed in with the steel so as these diamond masonry drill bits for concrete wear down fresh diamonds come to the surface so it doesnt go dull until you eventually wear them out. Can be used with 7/16 Hex Diamond Core Bit Arbors or SDS Plus Core Bit Arbors as long as thread size is 5/8-11 UNC - Same as a 5/8" Thread on an Angle Grinder etc. These bits are not dry diamond core drill bits so make sure to use them wet, a running hose directed at the core drilling bits while in use is best. Other Sizes Available 5/8" Diamond Core Drill Bit, 7/8 in Core Drill Bit, 1 inch Core Bit, 2 inch Diamond Core Drill Bit, 3 inch Core Drill Bit, 4 in Core Drill Bit, 5 inch Core Drill, 6 Diamond Core Bit