1、LONG LASTING BATTERY LIFE: Wireless calling system has a built in high capacity lithium battery for long life without frequent charging. 2、PERMANENT CALL RECORD: Call records are permanently saved, even if the power failure, restore the factory, call records will not be lost. 3、BUILT IN 33 TYPES OF CALLER RINGERS: Wireless pager watch receiver has 33 built in call ringers, which can be set freely to adapt to different usage scenarios. 4、LCD DISPLAY: Wireless waiter calling system adopts LCD screen display, humanized menu operation, easy to use. 5、MULTIFUNCTION DESIGN: Wireless waiter calling system adopts vibration, ringing and perpetual calendar display. Item Type: Wireless Waiter Calling System Material: ABS Watch Receiver Parameters Number Of Connected Pagers: 500 Alert Mode: Vibration, Beep, Blinking Receiving Sensitivity: -110dBm Call Information Storage Capacity: 20 Groups Battery Type: Lithium Battery Battery Capacity: 250mAh (Included) Standby Time: 7 Days Push Button Pager Parameters. Operating Frequency 433.92MHz Battery: DC12V Battery Type: Alkaline Battery (23A 12V Battery) Single Pager Battery Capacity: 60mAh (Included) Transmit Current: 10mA±3mA Standby Current: <1uA Open Distance:>200m / 656.2ft Keystroke: 1,000,000 Times Waterproof Rating:IPX4 Operating Temperature: -20℃-55℃ 1Key:Call 1 x Watch Receiver 10 x Pager 1 x Charger 1 x Charging Cable 1 x Instruction Manual