These quick release knobs are included with purchase of the MT1 or MT2 and will replace any current M12x35 bolt attaching the rod end bearing to the base swivel. Add them to the back if you are in need of a "no tools" way to remove your tower from the boat. If you need to replace the front set they will do that as well so you can continue to fold your tower down with ease. Includes the black quick release knobs and retaining lanyards only, it does not include the aluminum base assembly or heim joint. The base assembly is not sold separately from the tower. The Quick Release only works on the Monster Tower and will not work with other brands of towers.