As a novice at routing, I was puzzled for a while when I bought router bits that would not fit through the hole in the router base. Lo and behold, after reading an Amazon review I learned that you could buy an optional sub-base with a larger whole that would accommodate larger bits. I needed to round the edge of a 1" piece of oak, and the rounding bit has a "shoulder" that needed to be above the work surface. So the larger hole in the sub-base enabled me to raise the bit so that only the curved portion engaged the wood. Evidently the thinking behind the smaller hole is to make the router more stable for hand-held use, but I found it no problem to work with the larger hole. I totally agree with whoever said that this base should come standard with the router - with as much as router tables cost, you need this flexibility to maximize what you can do in the hand-held mode.