Features:1) Tapered connection: 6°, 7°, 12o 2) Threaded connection: R22, R25, R28, R32, R38, T38, T45, T51 3) Diameter: 30-127mm 4) Available types:a) "Retrac" button bits b) Drop center button bits c) Flat button bits d) "Retrac" drop center button bits e) Reaming bits Packaging: wood or plastic box package