The router assembly is made up of the column, column bracket and router bracket. The router can be moved to any height and any angle in the X, Y and Z dimension. The router will fit upside down if you need the opposite rotation. The has 1/2" and 1/4" collets. I find I'm using 1/2" boring bars with 3/16" square high speed steel bits the most. A critical element allowing use of the router is the separate variable speed controler. It allows adjustment of the speed to whatever you want. Without it the router will run much too fast for these boring bars. I run it around 1000 RPM most of the time.