Iron Man Mark IV

The Mark IV armor is the first shown armor in the second film. The suit has a differently-colored HUD, although its full arsenal and fighting potential is not explored in the movie. When it was shown on display within Stark's workshop, the Mark IV was labeled "Awaiting Upgrades" above it. The helmet is also shown to be removable as a single piece, evidenced by it sitting next to Tony while he eats donuts in the Randy's Donuts sign.