... used high precision steel core tube.Our Diamond Core Drill Bit are widely used for professional works.Sizes & Specifications are adjustable ... 600mm.Available all kinds of connection thread, such as 1/2"BSP, 1-1/4"UNC, 5/8", PIXIE, M16, ... 1-1/4” UNC30Rim or 3, 4300/450/500/1000R1/2” or 1-1/4” UNC32Rim or 3, 4300/450/500 ... /1000R1/2” or 1-1/4” UNC34, 353, 4300/450/500/ ...