Molded from non-flammable Polycarbonate. Virtually unbreakable, with high structural rigidity, long-term form retentionand superior impact and abrasion resistance. Screwless mid-size duplex receptacle plate, clearly marked top edges, clipeasily into place with gentle pressure. Mid-sized to cover wall imperfections and large wallboard openings. Mid-size - 4.875" x 3.125".