Check the listing for details. OFF SET BORING HEAD. Condition: Used. Listed at 299.00 USD. The OFF SET BORING HEAD is a toolholding adapter specifically designed for CNC machines in the metalworking industry. It allows for more precise and efficient boring operations by providing a stable and secure chuck for holding borers in place. This innovative tool adapter helps to improve accuracy and productivity in machining processes, making it a valuable addition to any workshop or manufacturing facility.