Note: This wireless Chuango 315Mhz WS-105 siren only can work with the 315Mhz alarm panel(G5/A11/B11/H4 Plus), can't work with the 433MHz alarm panel. Features: The WS-105 is completely free of wires, easy installation. Piercing 90dB siren. 3.7V rechargeable lithium battery, more power saving. Compatible with Chuango 315MHz alarm panels(G5/A11/B11/H4 Plus) and sensors, such as remote controls, door/window contact sensors and PIR detectors, etc. When connected to an alarm system and an intrusion occurs, the WS-105 will sound with the strobe light flashing. It is an effective crime deterrent. Specifications: Power Supply: AC 110V ~ 220V Maximum Siren Volume: 90dB Backup Battery: 3.7V 600mAh rechargeable lithium battery, 2.22Wh(included) Alarm Current:Static Current:Radio Frequency: 315MHz Housing Material: PC+ABS plastic Item Size(L * W * H): 90*90*42.2mm Package Size: Approx. 12.5*12.5*6cm / 4.9*4.9*2.4in Package Weight: Approx. 160g / 5.6oz Package List: 1 * Wireless Indoor Siren