Hi Jim...what James said is quite right. I had one of those router table-tops which went on the MK3, and the black plate has slots in it. Slide the clips all the way out to the outer edge of the plate, center the router with the included plastic disc and slide the clips back over the lip of the router's base-plate. Tighten them up and off you go. Trust me, it really is easy. The black plate is called a chassis, and it should have a black plastic slider on each corner, eight slots (for the jigsaw AND the router) and the big hole for the router bits. Any hassles, let me know and I'll try to help further.