Just a quick side-guide of sorts, as I didn't include these with the relevant main guides, but here are the helmets worn by Ghost and Soap during the opening mission we are introduced to them in.
Both are mostly the same, but with small differences. The relevant guides for Soap and Ghost can be found by clicking on their names.
Anywho, here are their helmets!
Future side-guides will probably focus on common details or smaller, less significant features like headwear or additional one-off accessories.
And please share this (and past and future) post around, so as many people can see it as possible. I want to share and spread this knowledge with as many as possible!