These cells are very special and application specific, these are the cells that still are in the solar arrays of the international space station, still in service 20+ years. The cell chemistry is BJT, Gallium Arsenide over Germanium. ​They generate a low voltage (0.55V) but a very high current (2A) per cell, perfect for use in high current, low voltage applications, their survavibility is beyond question and their EOL degradation level is very low at 20+ years later. We have 200+ units available.