●Standard voltage: 24VDC
●Standard current: 300mA
●Adapt voltage: 20-28VDC
●Sound pressure: ≥112dB (Environmental noise 65dB, 1 feet)
●Operating temperature:-10℃-50℃ ●8 kinds of sounds or tones, suitable for many different emergency places,such as firefighting,ambulance,burglar alarm etc.