Detailed Product Description Telephone & alarm system.It is integrated with home, business store, public ... round pins, two flat pins ,three pins , customerized3. Wireless receiving distance in open place: >120m, indoor: 30~50m, (depend on the ... , external siren: 110~120 dB6. One control panel with one telephone line and internal siren: working voltage:9 DCV, 500mA.7 ...