The Fast Stack Pro-G Hub is a revolutionary product that allows you to easily install and connect avionics into an existing aircraft or one you are building. The Fast Stack Pro-G Hub was designed to accept and connect most NAV/GPS/COM, modern audio panels, intercoms, VOR indicators, moving map displays, and almost any send/receive RS-232 formatted device. Approach’s custom cables are made to connect with the Fast Stack Pro-G Hub and associated avionics and come with connectors installed. Approach Fast Stack Systems