Feature 1Made of flame retardant ABS plastic, sturdy and durable to use. 2Microcomputer intelligent control and steady performance. 3Connect 12V power supply, automatic stroboscopic. Need to distinguish between positive and negative, red to positive, black to negative. 4110dB sound volume, to make sure you can hear the alarm sound at anywhere in your home. 5Suitable for security guard booths, gates, roads, tunnels, airports, construction sites as warning lights. It can also be used as photoelectric alarm output of alarm host.Features: Red and blue two colors for your selection. Made of flame retardant ABS plastic, sturdy and durable to use. Microcomputer intelligent control and steady performance. Receiving alarm signals, alarm with loud sound and flash. Connect 12V power supply, automatic stroboscopic. Need to distinguish between positive and negative, red to positive, black to negative. Suitable for security guard booths, gates, roads, tunnels, airports, construction sites as warning lights. It can also be used as photoelectric alarm output of alarm host. 110dB sound volume, to make sure you can hear the alarm sound at anywhere in your home. Specifications: Color: Red, blue (optional) Working Voltage Range (VDC): 6-15 Rated Current (mA): 300 Rated Voltage (VDC): 12 Sound pressure (VDC): 1103 Size: 12.5*7.5*4.5 cm/4.9*3.0*1.8in Package Weight: 118g/4.2oz Package List: 1 * Acousto-optic alarm 2 * Screws