CPG Signals Model ASHH PowerTone Amplified Speaker is designed for use in hazardous locations. The unit produces a crisp, clear, high-decibel tone. The tone may be generated by the PowerTone Signaling System of by a compact, solid-state, plugin card. The speaker cone and projector are of spun aluminum. The circuitry and tone card are contained in dust and moisture proof sealed housing of die-cast aluminum. An internal gain control allows for volume adjustment.