How it work of restaurant waiter call system

When the guest need help, can press the call button on the table. This signal will send to the receiver, such as waiter watch and number screen on the wall. Waiter will go to serve in timely if hear the prompting by sound or vibration.

Specification of Table call button with power bank

Power bank to charge the phone
Have a lighting when you press
2 key: Call; Cancel                                                  
Signal Distance: 200M in open area     
Material: high quality PC+Acrylic
Base Color: Black
Base Dimension: 160*77*59mm
Menu Board Size: 212*132*5mm
Battery capacity: 8000MAH
With 4pcs 18650 Li-ion battery
Input power: 7-12V
Output power: 5V/1A

This table button need work with wireless receiver