This product is no longer for sale, it has been replaced with Li-Po Rider.The solar charger is a stackable shield to Arduino compatible platforms, enables adaptive battery power and act as energy harvester for in-field charging. You may use various batteries just to shift up for 5V output, or put on Li-ion battery and solar panel to form an autonomous sensor unit.Charging:Auto adjust charging current according to source capability Designed for inconstant supply like solar panel Optimized charging curve for Li-ion batteries Charging status indicatorSupplying:4.4 - 6V input voltage 5VDC regulated output Max 500mA output Max 87% conversion efficiency Build-in 1A over current protection Documents:Datasheet