The two WindyNation 100 Watt Solar Panels allow you to start producing free, clean power from the sun! Perfect for RV’s, boats, cabins and back-up power! Two WindyNation 100 Watt Solar Panels can be wired in parallel to increase charging current (amps) for 12 volt battery charging. Or the two WindyNation 100 Watt Solar Panels can be wired in series to increase the charging voltage for 24 volt battery charging. SEE PICTURES IN PHOTO GALLERY ABOVE FOR ALL TECHNICAL INFORMATION AND DIMENSIONAL DRAWINGS.