Safety Technology International, Inc. STI-14200NC Universal Stopper Low Profile with Surface Mount with Conduit Knockouts, Indoor/Outdoor Clear Multi Purpose Protective Polycarbonate Cover Indoor outdoor low profile cover for surface mount protects against vandalism and accidental damage Protects pull stations keypads intercom stations emergency buttons electrical light switches duplex plugs etc Cover molded from thick tough polycarbonate material High strength continuous hinge Three year guarantee against breakage of the polycarbonate in normal use.