Why do I have these?

For some reason I have the Scanner and Strider helmets even though I didn’t do anything. All I did was enter every one of my pre order codes (and the helmets weren’t included mind you) and I go to change my spartan, and I have Strider and Scanner! any thoughts on why that happened?

map pass bonus

Yup, same here. I bought the limited edition and the map pack pass code that came with gave the helmets.