AK-D40A is a smart portable solar DC power system to use it, you are expected to unfold the folded solar panel and to properly put the stand in place with an inclining angle of about 40 and with the front face of the solar panel exposed to the sun, which enable the conversion from the solar radiation energy to DC energy and the latter is to be stored within the battery by means of controller, This system is suitable for travel in the small power lighting & electrical equipment power supply. It is especially suitable for areas without electricity or power shortage areas. If the sunlight is sufficient, the system should be full charged. When required, the system can supply the power to DC equipment.