Built on the success of the original Cellpro 4s charger, we re-released this version based on requests from satisfied, long-time Cellpro 4s charger users. But we went beyond a simple re-packing and re-labeling of its predecessor. With all new electronics, a plastic back for improved reliability, coupled with free Charger Viewer Software and free internet firmware updates, the Cellpro 4s GOLD represents an exceptional value in the 50W charger class. Node only operation eliminates the need to connect up additional red/black discharge leads. Extremely simple setup and operation; just plug it in and the charger does the rest. With the FUIM3, the Cellpro 4s GOLD charger supports 2 way PC communication for firmware updates, and 1 way PC communication to view charging information and charge graphing on your Windows PC.