Designed for use with Linear’s access control products. The Model ACT-34B is a four-channel device supplied with a quick-disconnect key ring. Also included are lithium batteries with a five-year service life. A unique 10-second time-out feature prevents the system from being shut down by a single transmitter transmitting continuously. The transmitter is in MegaCode format, which means each transmitter is factory preprogrammed with one of over 1,000,000 codes.