102mm Diameter R32 Thread Connection Cross Rock Drill Bit With YK05 Carbide Grade For Drift Excavation Manufactured by Henglong Rock Drilling Tools Factory, this R32 threaded cross drill bit is offered in a full diameter range from 45 mm up to 102 mm, built specifically for drift excavation and tunnel boring operations. Technical Specifications Diameter 102 mm Thread Connection R32 Carbide Grade YK05 Unit Weight 4.5 kg Flushing Ports 1 central front port + 4 side ports