I have a MacBook Pro A1278 MB990LL/A Laptop, I am trying to buy another power cord for it so that I don't have to keep moving the power cord from room to room. So far I have spent the better part of a day researching model numbers and parts and I cannot figure out what I am supposed to buy. I got all of the numbers from the power cords, which are the MagSafe Power Cords model number says a1330 60w, but it also says another model number ADP-60AD D, and then the extender model number is ACP7Q, I can find the extension cord but I am confused by the magsafe adapter. The internet seems to indicate that I am looking for two different ones. And when ever I search for the a1330 adapter it doesn't mention anything about compatibility with the A1278, it doesn't mention it at all I don't think. Can someone please help me with this. I don't want to order the wrong cord. I just want to be able to use the computer without having to move the power cord. Thanks.