Over at
capt_america I posted something related to this a few minutes ago, but this is more of a this community question.
End of the last Iron Man film we see that James Rhodes is now using the Iron Patriot armor, that's what his War Machine armor was converted into, and Tony made a big thing about not being able to let Rhodey wear any random armor as they're all coded to Stark's brain patterns.
So, when the Avengers are all trying to lift Thor's hammer and Stark pulls on a gauntlet & Rhodey lends a hand, what's that on his arm? Don't see any red, white, & blue so it's not his armor...