The KanexPro High Speed HDMI cables with Ethernet are designed with built-in booster for applications that require high-performance transmission of HDMI digital video and multi-channel audio signals. These cables have active amplification built-in to prevent impedance mismatch caused by the cable attenuation dielectric losses and compensation for skin effect over long distances. For flawless transmission the output of the cable is placed at the end of the display to amplify full signal transmission with zero signal loss. The built-in booster does not require an external power since it is using the 5-volt from pin-18 on the HDMI cable extracting the power from the display. These cables are fully CL3 certified which surpasses any in-wall code requirement for residential or commercial installations