The Wheelock Eluxa weatherproof series EL3RSPK/EL4XSPK speaker and EL3RSPST/EL4XSPST speaker-strobe appliances are designed for easy installation with a pre-wire capable EL3RBB mounting plate, or EL4XBB back box. All Eluxa weatherproof models are for indoor/outdoor use and wall or ceiling mount. The EL3RSPK/EL4XSPK and EL3RSPST/EL4XSPST Series Multi-Candela Speaker Strobes are designed for multiple power requirements with high dBA output at each power tap. The design incorporates a high efficiency speaker for maximum output at minimum power across a frequency range of 400-4000 Hz.