Thanks to this switch , you can plug 3 scart devices (DVD players, video recorder,…) to another device (TV, video projector,…). On the exit there is one scart and one 3 pins Cinch exit (video, right sound, left sound). Another 3 pins Cinch plug indicates the TV exit signal.3 scarts switchThe devices can be plugged thanks to the scarts or the Cinch plugs.Device choice over keys