Intermittent visual alarm for alert of unauthorized exits or entrances through emergency doors. Low battery warning indicator. 3 mm Polycarbonate- Powered by 9 VDC alkaline battery (or 12-24 VDC by cable). Sound power 95 dB – low / 105 dB – high, Dimensions:. 136mm wide x 136mm high x 50mm. deep. Working temperature; 0°C to 45°C, Red color.