Fallout: London, a fan game built using Fallout 4, has added a rather unique method of keeping your rad count down. As some players have discovered, the "Jimmy Hat" item actually increases your resistance to radiation, somehow.
And yes, Jimmy Hats are exactly what you think they are - hats for your Jimmy. Otherwise known as johnnies, raincoats, rubbers, or, you know, just condoms. Somehow, popping one of these on decreases the amount of radiation your character builds up. Incredible stuff.
Shout out to Reddit user CWalkthroughs for spotting this neat little feature. I guess it's keeping... part of you safe from being exposed to nuclear fallout, so that could explain why it's so effective against radiation.
As highlighted by Reddit user RelativeWeekend453, these were also an item in Fallout 2, so it's not just thrown in there because it sounds like something a Brit would call a condom. However, in Fallout 2, they behaved like actual condoms and were there to stop you from getting another character pregnant if you slept with them. Don't worry - future Fallout games didn't make you worry about that.
Fallout is intrinsically American, but Atomfall brings the post-apocalypse to British soil...