... homes, clubs, etc. Wireless Calling Service System / Table Calling System / Hotel Service System:Main function:(1) The system is made up of one receiver ... , factories, nursing homes, amusement parks, clubs, families, etc.(3) Working radio frequency: 433.92mHz;(4) 32 musics;(5) Receiver size: 29.5 ... , worker, sickbed, or other places you can use this calling system.