VeLLBox SDI Switcher 4x1, 4 in 1 Out SDI Switcher, Support Resolution up to 1080p, 5V/2A Universal Power Adapter, Grey Switches four SDI signals to one SDI monitors simultaneously, that makes you are able to choose any one of them This product is specially designed with equalizer IC in its input and drive IC in its outputs. All of the input and outputs support long coaxial cable The input signals can be switched by the button. While with RS232 interface, you can also switch the signals via computer system Compatible Devices: HDcctv1.0, HD-SDI (ST 292), 3G-SDI (ST 424) and SD-SDI (ST 259) Package Contents: Main Unit X 1, Universal Power Adapter X 1, Users Manual X 1