20W Solar Panel and Fittings. Flexi PV solar panels are tough, fully weather resistant flexible panels designed for use in the harshest environmental conditions. Great for small power consumption projects and perfect for use in boats and caravans during weekend trips. The 20 watt kit provides a continuous trickle feed maintaining and extending the life of any 12 volt battery. Fitted with a blocking diode to prevent reverse current drain. The Flexi PV Roof Top Kit comprises all the essential items to permanently mount a Flexi PV solar panel to the roof or deck of a motorhome, caravan, boat, yacht or narrow boat.