RADIO FREQUENCY TECHNOLOGY HAS TRADITIONALLY BEEN USED TO REMOTELY CONTROL BARRIERS, AUTOMATIC GATES AND DOORS BY UTILISING HAND HELD TRANSMITTERS AND REMOTE RECEIVERS. THE LATEST FAMILY OF PRODUCTS INCLUDES INDIVIDUALLY CODED HAND TRANSMITTERS TOGETHER WITH COMPACT RECEIVER/CONTROLLERS THAT CAN LEARN AND STORE UP TO 10 HAND TRANSMITTER CODES PER CHANNEL. THE TRANSMITTERS USE THE UK APPROVED FREQUENCY