The vs421hd4k 4 port hdmi 4k switch lets you share a display or projector with four hdmi enabled audio video source devices the switch features four independent inputs that each support 4k resolution and 71 surround sound audio the 4 port switch also features mhl support on hdmi input port 1 enabling video output video from mhl enabled mobile devices such as samsung galaxy tablets and smartphones astonishing picture quality with 4k support yoursquoll be amazed at how this video switch