Featuresr 2 av input sources 1 av output sources easy to switch between two alternative audio and video sourcesr av input includes primary and secondary audio and video and the primary input av l1 r1 v1 is priority the secondary input av l2 r2 v2 is standby when the two av signal are available it will switch to secondary av signal if the primary is not availabler 2 av signal input could be switched by button easilyr perfectly suitable for in dash dvd headrest dvd front view