All Apple iOS devices have a Model number which looks something like this: MC605LL/A. The MC605 is an iPhone 5, black, 32GB. You can find these numbers on the Models page. The two letters behind it, LL in this case, specify the region code.
Sample Part Number / Sales Model: Your Part Number is ( MQ3E2 ZP/A )
Questions: How to Find Part Number?
Answers: You can find part number by 3u Tools easily.
No.1 First go to the Download_3utools
No.2 Connect your phone with 3u Tools software