The Original (Grey) Armor..
The Grey armor was built around an iron chestplate designed to prevent a piece of shrapnel Tony had received in Vietnam from traveling to his heart and killing him. The armor, made from ordinary iron, provided protection from physical attacks, small arms fire, temperature extremes, some energy forms, and acid.
The exoskeleton boosted the strength of the wearer by about 10 times. Air pressure jets allowed for extended jumps, but not true flight. Weaponry included a chest-mounted monobeam, a miniature hacksaw that extended from the gauntlet's fingertips, and magnetic turbo-insulators that allowed Stark to magnetically deflect metal projectiles or bring metal objects to him. All of the armor's devices and functions were manually controlled by the wearer..
C'mon... Any self-respecting Iron Man thread has to have the original armor somewhere in it. 😛