Rev-A-Shelf's fillers revolutionized otherwise wasted space in your kitchen. Normally a "filler" or extra space is simply covered up with a decorative front, but with Rev-A-Shelf's towel bar fillers, it turns that otherwise waste space in to useful space to store your kitchen towels and cleaning supplies. Fillers are intended to be installed in new kitchen cabinet construction and will not work in existing cabinets. These units feature a soft-close which is a upgrade from our normal 432 ball bearing slides.