Molded from non-flammable Polycarbonate. Virtually unbreakable, with high-structural rigidity, long-term form retention and excellent impact and abrasion resistance. Screwless mid-size duplex receptacle plate, clearly marked top edges, clip easily into place with gentle pressure. Mid-sized to cover wall imperfections and large wallboard openings. Mid-size - 4-7/8 in x 3-1/8 in.