The ideal choice to prevent battery drain. The 5W panel provides a continuous trickle feed maintaining & extending the life of any 12V battery & delivers approx 32.5 Wh per day. The 5W solar panel is fitted with a blocking diode to prevent reverse current drain & is supplied with all the necessary cable (4m), connectors & detailed installation instructions. NOTE – The 5W panel kit does not require a charge controller if the battery to be used is larger than 35 Ah