JoyTech 3w 6v 500ma Solar Panel Module Solar Epoxy USB Charger 190&times;175 Module Solar System Solar Epoxy USB Charger Build your DIY powered models/solar toys / solar displays Size: 1901758mm It can be used for teaching purpose. Many of our customers comes from school,colleague,etc. If see any advertisement said can charge iPhone, that's false advertisement, please be attention When the voltage of your solar panel don't satisfy your storage battery, you can take two or more same solar panels together in serices. Such as,two 5.5v solar panel take together in serices, so its voltage is 11V. when the voltage of solar panel satisfy your storage battery. In order to Speed up the rate of charge, you can take two or more same solar panel together parallel connection.