Dead iPod nano, 5th generation. How do I determine the memory?

I've owned my 5th generation nano, model no: A1320, since 2009 and it died a couple of months ago. There was nothing wrong with it. I'm pretty sure the battery just needs replacing. My question is, how do I determine if it was the 8 vs 16 GB nano? This is something I should know but it never crossed my mind since I played the same 100-200 songs anyway.