Continuity mistake: When Pepper is watching the television program about Stark Industries' stock troubles, after Tony's press conference, notice she has a wireless headset in her left ear. When Tony calls her down to the lab, the camera flashes back to Pepper and the ear piece is gone. (00:48:50)
Visible crew/equipment: In the extra footage after the credits, the reflection of the crew is visible in the picture frames around the apartment.
Continuity mistake: When we first see Tony Stark arrive at the benefit, his car doesn't have a front plate. When we actually see him pull up to the entrance though, his personalised "Stark" plate has appeared.
Continuity mistake: After Stark is paralysed and slightly recovers, he goes to get his energy. Right then the blood around his left ear has vanished. Being seconds away from dying, the last thing he would think of is taking a shower.
Trivia: Stan Lee makes his usual cameo, this time seen as a man who Tony Stark mistakes as Hugh Hefner. (01:08:05)
Continuity mistake: In the montage of Stark designing the Mark II suit on his computer, he picks up a coffee mug to his left and absent-mindedly drinks it, then gets a not-good expression as the liquid was presumably not what he was expecting. A second earlier, the coffee mug had been shown completely upside-down on the desk.
Character mistake: There is a misspelling on the cover of the issue of Forbes magazine shown in the presentation about Stark's life. It reads "Tony Stark takes reigns at 21". The correct spelling of the word is "reins". Stark may "reign" at Stark Industries but he would take over the "reins" of the company.
Chosen answer: It was basically a prototype made from, to quote Stane, "a box of scraps." It was not strong enough to last, especially when it came to powering Tony's high tech armor armor upgrades.
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