CMT 692.100.31 Universal Shaper Cutter Head, 4-Inch Diameter, 1-1/4-Inch Bore Heavy duty aircraft aluminum body, RPM between 5500 and 8400. For use knives with a height of 40mm (1-37/64-Inch) or 50mm (1-31/32-Inch). Pins for the automatic positioning of the knives and the limitors. For use on all types of shaper and spindle molder machines. Versatile, easy-to-use and cost effective solution to shaper work.