Atlona ATHD4V41 4X1 HDMI Switch with 3D, Arc and Ethernet Supports all video resolutions between 480i and 1080p as well as 640x480 up to 1600x1200 for the highest quality video from these sources Automatically switches to the most recently connected or powered-up source Activated using RS-232 adjustment Audio is returned from the remote display's internal tuner or from any device plugged into it via HDMI to the S/PDIF audio output Allows ARC-enabled TVs, such as smart TVs, to transmit audio back to an AV receiver through the same HDMI cable used to connect the input