Diamond Drag Engraving Bit for CNC Machines Use your CNC mill to diamond drag engrave plastics, brass, aluminum, steel, glass, and granite Industrial diamond engraves line as CNC machine drags the tool around the profile of your design Fits in any 1/2" collet, just like a regular end mill Engraved brass and aluminum plates for commemorative plaques, trophies, name tags, and monograms Engrave decorative glass, mirrors, and granite tile