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Thanks for the reply, much appreciated.

I should have been more precise. I'm looking to buy one from ebay. Are the 5.0 / 5.5 identifiable by serial numbers or year of production?

Thanks again!
S65

Here ya go!

iPod 5th Gen - Enhanced

MA444LL/A (30 GB White)
MA446LL/A (30 GB Black)
MA448LL/A (80 GB White)
MA450LL/A (80 GB Black)

iPod U2 5th Gen Enhanced

MA664LL/A (30 GB)

https://everymac.com/systems/apple/ipod/ipod-faq/ipod-nano-mini-shuffle-apple-model-numbers.html

Extremely handy website that one - 5.5 gens were also referred to as 5th Gen - Enhanced, as indicated above.
 
Thanks for the post, sammy. Very useful!!!

The easisest way to tell are the headphones. 5th gen iPods come with the old ones, with black sponges. 5.5 gen iPods come with the traditional ones that every iOS deviced had before the EarPods.
 
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