Will my iPhone work in the states?

I'm currently living in England but i'm moving over to the states till December and have an iPhone 5 (A4129).

I've been reading through articles online, and they're all really confusing.

I know my phone will work with some networks, but the way the articles are worded make it difficult to find out what i actually want.

Basically, my phone is A4129, what networks will it work on in the states, and will i get 4G or be limited to 3G?

Thanks