Model Number: ZJ-48 Brand Name: CallingSYS Key Specifications/Special Features: Receiver use RF wireless and learning code technology, can pair up to 48 wireless calling buttons and the receiver host adopts advanced microprocessor and high-sensitivity super heterodyne receiving technology which make the products very stable, also it has adjustable voice prompt, different calling records display and LED digital display functionsWireless calling system has millions of different code which can be paired easily and freely and it is widely used in restaurant, café, bar, tea shop, KTV, bank, office, factory, hotel and hospitalTechnical data: Working frequency433.92MHz Working voltage 9-12V DC/1A power supply Standby current 200mA Working current <500mA Decoding mode Learning code Modulation AM Receiving sensitivity -108dBm Working temperature -10 to +50C Product size 410*152*33mm