A gas-mask item that is compatible with current helmets would be a neat implementation. A first person gas-mask overlay would be neat as well. It wouldn't serve any real purpose other than IC reasons. Balaclavas would be cool too, to conceal identities. I don't have a problem with donating for these items to be added as cosmetic items if that's what's required, as long as it's a reasonable amount. I'd let anyone use them.