2-3/8" diameter discs move everything as if it had wheels. Move up to 2500 lb. Won't scratch your floors. Works on any kind of surface: Wood floors, vinyl, ceramic tile, and carpeting. Ideal to move entertainment centers, bookcases, filing cabinets, armoires, desks, wall units, and sideboards. Will slide over doorsteps or floor edges with a height difference of up to 3/16". Can be used over and over or attached permanently with the double-face tape provided (or epoxy or Crazy Glue Gel). Color: Grey. Contents" 4 sliding discs with adhesive. For all solid based furniture. As seen on TV.