i bought a RCA MM55 Universal Car Charger
http://www.radioshack.com/product/in...rt&tab=summary
It has an output selection of 5v @1000mA and the polarity is correct (you can change it based on the orientation of the tip). The voltage can only be changed with an included key or a small flathead screw driver.....so i think that eliminates the problem of accidentally changing the voltage
so from what I've read, it sounds like 1000mA will still charge a H120? the manual says "Do not use with any device that requires more than 1000mA of current" so is that a problem?
edit: sorry, i didnt even realize that the previous post asked the same exact thing