Working principle: This item uses 3 phase generator without carbon brush for high power, which adopts switching voltage reduction circuit to produce 800mA output current to charge the built-in 300mAh/3.6V Ni-Mh battery or come with a charging cable to recharge a mobile phone( while it does not recharge the inside battery). The green indicator is on when cranking the flashlight. The 2 position push switch is used to switch between 2 AAA batteries and the built-in battery via the voltage increase circuit to supply LED with power. The logic switch is used to control the working mode, i.e., two LED bulbs are turned on firstly and after, and the 0.5W LED on and then off. Product features 1> Crank by hand for power 2> Luminous flux>10lm, brightness>150000mcd 3> Big current to charge mobile phones 4> Waterproof Cautions in use: 1. Fully the plug the socket, otherwise it possibly leads to circuit shut off. 2. Crank it as even as possible (keep rotating steady). Too slowly cranking would make current weak and prolong charging time, and too violate cranking possibly damages the power transferring system. Keep cranking to charge a mobile phone continually, otherwise the power consumption will increase and affect the charging effect. 3. Pay attention to the holding gesture when cranking so as not to hurt your fingers. 4. In order to protect the battery'''