I had to replace the dc plug on the ac adapter cord recently. They Acer A100 dc plug is 3.0 x 1.1 (9mm tip length) from Philmore (LKG Home Page ). The plug size is not listed on their catalog, which is kind of strange. You need to go with the 9mm tip length because the tip will hang out and will bend/ break very easily. Most of the electronic supply companies want to charge you a $9 shipping charge for a $2 item. I was lucky enough to find it at Willy's electronics in SD.