This is an optional module which installs into a Yaesu FT-736r that enables transmission on the 1.2 GHz band.  It is normally installed in the bottom slot closest to the side of the radio to allow access to the jacks on the side if desired.  Includes the 4 mounting screws and the rubber pad.  This is easy to install as just 2 cables and a power wire are connected then restart the radio so it recognizes this option.