The MLCS heavy duty 15 Amp router motor is made to handle the largest router bits on the market. Cutting with a 3-1/2" diameter raised panel bit will be no problem. The variable speed range on this heavy duty router is 10,000 to 22,000RPM, so no external speed control is needed and it will handle all of your routing operations. Included with the motor are 1/4" and 1/2" collets plus 2 Offset collet wrenches. 4.2" Diameter Motor. No Base included.