we are a company specialize in the universal portable power recharger, it includes lithium polymer battery ,control circuit, and invert plug ,is to be used for all the laptop ,camcorder ,mobile , Psp ,iPod , Mp4 and etc. because it has 8 different voltage and current output ,you can use your laptop ,camcorder outdoor anytime and anywhere without the consideration of the power death. this product is very compact and conventient , you can take it with you when you travell, outdoor explore, business , or go to some place where is short of energy.