Clean Mat is a polyethylene film mat with a tacky surface that prevents dust and dirt from spreading while building or remodeling. Each mat contains 30 sheets which are tabbed for easy removal of each layer. When the top sheet becomes too dirty, peel it away to expose the next clean layer. Clean Mats are commonly placed outside of dust or lead containment areas, or used as a door mat when entering a building. Size is 24" x 45".