Our 900 meter Wireless Warehouse Long Range 'S' Bell System is supplied with a Heavy Duty Push Button and a Loud Bell. It is popular in many applications, such as: Warehouses, Schools, Factories, Farms & Rural Businesses and Large Homes. The transmission range between the Battery powered Wireless Transmitter and plug in Receiver is an impressive 900 metres (line of sight), which equates to around 400 - 600 metre in most applications, this can be at least doubled by adding the Signal Repeaters. How it Works: The Heavy Duty Push Button (with 'Please Ring' etched onto it) is connected to a Long Range Battery Transmitter (fitted inside a easy to mount weatherproof box) by 3 metres of bell cable. The Push Button would be mounted onto the most appropriate location and the transmitter box would be located into the lost suitable location for wireless transmission (this could be simply on the back of a post or just inside a factory wall). The Receiver is powered by a plug in Transformer and has a built in chime (with adjustable volume), this is connected to a 85 Decibel Bell by 3 metres of cable, the Bell is fully weatherproof therefore can be fitted inside a Warehouse or in the Yard. When the Push Button is pressed, the Receiver will activate the built in Chime/Buzzer and the Wired Bell, the standard duration options for the Bell activations are from 10 - 60 seconds or 5 minutes..These Bell Systems are quick and Easy to Install, Manufacturer: Ultra Secure