Bosch RA1161 Router Fixed Base New base for the 1617/1618 Series Routers Classic hardwood handles Coarse and microfine adjustment system with resettable depth indicator- For fast, precise bit depth adjustment Large 3-3/4-Inch base opening and 2-Inch subbase opening - Accepts larger bits, and provides better viewing visibility Precision Centering Design - Makes it easy to keep bit on intended cutline when using jigs, templets, dovetail fixtures and similar guidance devices