Unfortunately, Shen Hao didn't research the fact that there are standard sizes now for almost everything. This is curious, as they were able to copy the graflok back pretty well. In any event, they do not have an opening size in the front of their compendium lens hood which will accept "normal" filters. I've been using screw mount lens filters, so it isn't a problem for me, but if you are planning on using the 4x4 Lee filters, they are too small. Some sort of adapter must be made.
As doughowk has said, there is a metal plate which screws on to the top edge of the front standard. There are three holes in the metal plate, two which use wood screws to fasten the plate to the camera. A hole must be made in the standard for the threaded part, which screws into this plate, the center hole. An electric drill with small bits and a screw driver are all that is needed for this hood to be mounted properly. There is ample movement in the hood. I use mine with the 240mm g-claron to cut down on light bouncing around inside the camera (lens covers 8x10). It is a decent deal for the money, given the limitations of filters. tim