Which model is my old iPhone?

Hello ~ I think that is actually an iPhone 5 but take a look here:

Identify your iPhone model - Apple Support

~Katana-San~

wwengren wrote:

I have an old iPhone that I kept in storage. The model nr is MD638LL/A. I would like to see if I can turn it in for a few dollars. Which model is it, e.g. iPhone 6, iPhone 7, 8, which?

Find the model number of your iPhone, iPad, or iPod touch - Apple Support