Dia 7/16" - 4" (12mm-100mm) D.O.P 1",2",or 3" (30, 50, 75, or 100mm) weldon shank ... ,75,100mmweldon shank/one-touch shank 19.05mm 3/4",1 1/4" made of hardened H.S.S, cobalt steel. TiAIN ... , lathe, etc.We also have Pilot Pin and MT Holders High Performance High-Speed Steel Annular Cutter