Concrete core drilling – 102mm diamond core bit. Drill holes in concrete, brick, masonry and stone with a 102mm diamond core bit. The 300mm length and 1-1/4 UNC connection help you select the correct size and fitting for your core drill. Laser-welded diamond segments. Designed for wet drilling. Suitable for concrete, reinforced concrete, brick, masonry and stone. Thread: 1-1/4 UNC. Segment type: laser-welded diamond. Confirm the diameter, working length, thread and wet-drilling requirements against your machine instructions. Use suitable water supply and follow the instructions for your drill and core bit. 1 × FIRMIX 102mm diamond core bit.