About this item IMPORTANT 1: This is an HDMI Splitter; it cannot switch the signal between devices. Please plug your Computer/Laptop into the input port, connect your TV/Projector to the output port, and then connect the power adapter. IMPORTANT 2: This HDMI Splitter cannot extend the screen; it can only mirror or duplicate one signal to 4 TVs, displaying the same content. (Supports A-AAAA mode; cannot support A-ABCD mode) IMPORTANT 3: This HDMI splitter does not have a separate audio interface; it will not produce sound unless the output device is connected to a TV or monitor with built-in speakers. IMPORTANT 4: Please use 4K or higher quality cables to ensure stable transmission. Additionally, the maximum supported cable distance for input and output is 15 meters each. If the distance exceeds 15 meters, please use 8K fiber optic cables. We do not recommend using excessively long cables. 4K HDMI splitter 1 in 4 out: This HDMI splitter can mirror/duplicate 1 HDMI input source to 4 HD o