Dodge Nitro after market in dash radio thing ...?

[Renee]

OK, I admittedly DO NOT KNOW much about cars or their accessories. That being said ... I bought my boyfriend a really cool new radio for his car, screen flips out, had a back up camera thing, usb and memory card slot ... yeah ... well I bought this for his old car, his Pontiac Grand AM ... the day before I was going to give him this awesome new thing, he bought a Dodge Nitro. He said that radio can't go in his car because of something or other ... well that was supposed to be his birthday present in February. Well now our anniversary is coming up and I would love to buy him another radio that actually fits the Nitro. I would like one very similar to the one I got before ... is there any way of finding out what stereos will fit the Nitro or ... what? I have no idea how to word this lol ... so hopefully some people who know cars and stereos can help me out. I figured it might have something to do with the fact that the Nitro is American made ... maybe I need an American made stereo? I don't know. PLEASE HELP!!! I'm trying to be an awesome girlfriend here!