The HEX70ARC-KIT 4K HDBaseT ARC extender set offers market leading features for the custom installation industry. The product delivers HDMI ARC Optical Audio Return Bi-directional IR and Bi-directional PoC (Power over Cable) up to lengths of 70m (40m at 4K 60Hz 4:2:0).N/AN/A<b>Advanced Audio Return Channel (ARC) Functionality</b>N/AThe three modes for Audio Return and CEC are controlled using the switch located on the Receiver unit. The switch positions are HDMI PASS or OPT. See below for explanation:N/AN/AHDMI - HDMI ARC in to the Receiver from the display to Optical Out and L/R Out on the Transmitter. CEC communication over HDBaseT is blocked.N/AN/APASS - HDMI ARC in to the Receiver from the display to HDMI ARC Optical Out and L/R Out on the Transmitter. CEC communication is passed through the HDBaseT link.N/AN/AOPT - Optical audio in to the Receiver from the display to Optical Out and L/R Out on the Transmitter. CEC communication over HDBaseT is blocked.