best price of wireless calling system for elder, one to one

This wireless calling system is used for one person to call another person. Widely used in office, home, factory and supermarket The home alarm system consist of a call button and the signal  receiver. When an elderly or disabled in panic or emergency situation, he or she can press the button near him or her, (The button could be worn on neck or fixed on the bedhead or stick on table), then the signal receiver will work with sound to attrack attendant's attention.    This system could be used in many kinds of field. Such as home, parking lot, school, hospital and so on... 

 

 

 

 

 

best price of wireless calling system for elder, one to one