Jacobs 7318 AO306 Arbor Adapts No.3 Morse Taper to No.6 Jacobs Taper Precision machined and ground to master gages for maximum performance with Jacobs drill and tap chucks Adapt Jacobs taper to Morse tapers, straight shanks, threaded shanks and Bridgeport tapers Ideal for use with custom tool and work holder designs and for specialized machining applications