Small solar panel with 5V nominal output voltage at max. 100mA output current.
Such a small panel can power your microcontroller project, charge a battery, and drive a LED light bulb or a small fan... How about a base cap with a solar panel and fan blower to make the hot days bearable?
The dimension of this panel is 84.5 x 62 x 3mm, and the weight is about 16g.
Please note: When soldering wires to the contacts on the back, please make sure you do it quickly. Too much heat for a long time can cause damage to the panel.