The FBA-38 is an alkaline battery tray designed to provide an alternative  means of powering the HX-700 series of radios when the main battery has gone flat and no charging facilities are available.

The FBA-38 is an alkaline battery tray designed to provide an alternative  means of powering the HX-700 series of radios when the main battery has gone flat and no charging facilities are available. The FBA-38 will take 5 x AAA cells.