CPG Signals Model SPHX Powertone® Explosion-proof Speaker is designed for use in hazardous locations. The unit produces a crisp, clear, high decible tone/voice output on any 25 Vrms or 70 Vrms tone/voice audio system. The speaker cone and projector are of spun aluminum. The speaker driver and circuitry are contained in an explosionproof housing. The speaker has a supervisory DC coupling capacitor and wattage taps from 0.5 to 15 watts. The speaker is listed for indoor or outdoor use, is NEMA 3 rated, and is finished in red enamel. The PowerTone® speaker is designed for connection to system supervised alarm notification circuits. Weatherproof corrosion-resistant surface mount speaker is required.