Just thought I'd share this info. I purchased this car adapter off of eBay a few weeks ago and I finally found out why it does not work with the ACER A100 (as it is described to do). This adapter does not regulate the output voltage. It puts out whatever the car puts out, which is more that 13 volts with the engine running on my 2009 FORD F150. When the engine is not running, the car cig plug puts out less than 13 volts and then this adapter does work with the ACER A100. But, since 99.99% of the time I want to use it when the engine is running, this adapter is of no use to me. I used a voltage meter to perform my tests and verified the voltage outputs when the adapter works and when it does not. Another car adapter that I have DOES regulate the output voltage to below 13 volts and it works perfectly with my ACER A100. SO, I'm just saying, don't expect this particular DC Car adapter to work with the ACER A100.