Replacement Battery for Marinco Nicro Solar Air Vent Part Number N20790
West Marine Part Number 297534
This is an equivalent battery to the original, rated at 1.2 volts and 2800mAH         $15.97

High Capacity version, 1.2 volts 5000mAH                                                         $21.66
marinco nicro vent battery N20790 west marine 297534