With this module it is possible to set up an infrared light barrier with a maximum distance between the transmitter & receiver of a huge 30 metres nearly 100 feet Breaking the beam throws a relay 24V 3A 250V 1A which could be used to switch an appliance such as lights alarms etc. The transmitter requires a 9V 50m A power supply & the receiver requires a 12V 100m A power supply.