The Jacobs BT 45 - JT5 Tool holder Adapter is designed to be used on machining centers with BT 45 flange automatic tool changer. The Jacobs BT 45 - JT5 Tool holder Adapter has a No 5 Jacobs Taper mount and 5/8-11-Inch internal thread. The Jacobs Tool holder Adapter meets JMBTA Standard MAS 403-1982. The Jacobs BT 45 - JT5 Tool holder Adapter is manufactured from high-grade alloy steels, and precision CNC machined and ground to ensure high accuracy and close-tolerance fit. The Jacobs BT 45 - JT5 Tool holder Adapter is ideal for use with custom tool and work holder designs and for specialized machining applications. The Jacobs BT 45 - JT5 Tool holder Adapter comes with one year factory warranty. Warning: Tool holder retention studs are not necessarily interchangeable across various types of tool holders or machine tool models. Use of metric threaded studs in inch threaded holders or vice versa is dangerous. Failure to use the proper thread or stud configuration can cause the tool holder to come free of the spindle resulting in serious personal injury