Feature:1. Using radio frequency wireless technology, the system is stable and the wireless receiving distance is long.2. Fashionable appearance and novel design, display time, year, month and day, support 400 pagers, support single-button or 4-button pagers.3. Call button word selectable, accurate time display and 30‑level digital control volume adjustable.4. Can name the call button starting with ABCDEF, and use advanced micro‑processing chip to make its performance stable and reliable.5. Widely used in various places such as homes, hotels, bars, restaurants, factories, workshops, tea houses and offices.Specification:Item Type: Wireless Calling SystemDisplay Receiver Parameter Description: Model: SU-620Operating Frequency: 433.92MHzMaterial: ABSWorking Current: 100mA±10mAReceiving Sensitivity: 105dBmDecoding: Learning the codeWaterproof Rating: IPX4Working Temperature: -20℃~ 60℃Button Transmitter Parameter Description: Model: SU-A01Operating Frequency: 433.92MHzBattery Model: 23A12VBattery Capacity: 60mahEmission Current: 10mA±3mAStandby Current: <1uAOpen Distance: >500mKeys: 1 million timesWaterproof Rating: IPX4Working Temperature: -20℃~ 60℃One Touch: CallHow to Use: Button Function Description: Function Key: FUNConfirm Key: ENTDown Button: DOWNLeft and Right Buttons: MOVEUp Key: UPF3-2: Last stay display time 1-99 secondsF3-3: Cycle interval time 1-99 secondsF5-3: Number of reports 1-9F6-1: Delete all pagersF6-2: Restore factory settings (and delete all pagers)F7-1: Time setting.Package List:1 x Display1 x User Manual 1 x Power 30 x Transmitter30 x Sticker