Description :  KERUI F86 LED Wireless Square Nurse Waiter Restaurant Emergency Touch One Key Call Button 433MHz   Features :  This button is used for service call in the restaurant、 bar etc and nurse call \/ emergency call in the hospital. Delivers the instant message to the host monitor、 time-saving and labour-efficient. Blue light LED circled button. Low power consumption. Wireless signal transmit、 stable frequency、 interference-free. Works with the host receiver(not included)、 cable-free installation、 space-saving. Widely applied in home、 factory、 school、 bank、 store、 apartment etc.   Specification :  Operating voltage: 4.5V Standby current: ≤ 4UA Wireless Frequency: 433MHz Encode: HS1527 Adjust Method: ASK Powered by 3 pieces of AAA batteries. Wireless coding: PT1527、 EV2262 Wireless distance: 100M in open area 1 button: Call Size: 86 x 86 x 18mm   Package includeds :  1 x KERUI F86 Wireless Call Button 2 x Nail 3 x AAA Battery   Details pictures :