Switch between four HDMI sources on a single HDMI display, with support for MHL and video resolutions up to 4K. 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 7.1 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 SupportYou'll be amazed at how this video switch maintains Ultra HD picture quality. 4K is supported by the latest A/V devices and delivers four times the resolution of 1080p. Plus, because the switch is backward compatible with high-definition 1080p, you can rest assured any video source will look great in your digital signage application.Solid Aluminum Housing Ensures Fixed PositioningConstructed of solid aluminum, the HDMI switch is durable and heavy enough to prevent the unit from lifting or sliding around if the attached HDMI cables are bumped or shifted. Plus, its small footprint makes it easy to integrate the switch into any boardroom, classroom, home theater, or digital signage application.Hassle-free Operation with Auto SwitchingThis switch ensures effortless operation with automatic switching that detects and selects a newly connected device. Automatic switching encourages on-the-fly collaboration among colleagues, by making it easy to share your projector between multiple source devices in a boardroom or classroom environment. The VS421HD4K also supports manual operation using the included IR remote control, or the built-in front panel toggle switch directly on the device.The VS421HD4K is backed by a 2-year StarTech.com warranty and free lifetime technical support.