It was described by James Rhodes as "an unarmed prototype of the Iron Man armor".
After returning from captivity in Afghanistan, Tony Stark began designing the Mark II armor, drastically revamping the design of the Mark I using the resources and technology available to him through his company: Stark Industries. Tony started building this suit in stages, experimenting with new technology, mainly to improve the suit's flight capabilities. Working from his basement workshop Tony started by creating a pair of thruster boots, quickly followed by a pair of palm based repulsor gauntlets to stabilize his flight.
Once Tony had perfected the flight thrusters and repulsors he went on to create the armor of the suit itself, making it more sleek and aerodynamic than the Mark I, with articulated control flaps for added flight control and stability. He also created a user interface using his J.A.R.V.I.S. AI system. During his first control test, Tony decided to take the Mark II on its first full test flight despite J.A.R.V.I.S.'s recommendations. His flight proved to be an outstanding success until testing the suit's altitude limit, during which it demonstrated a near fatal icing problem in the higher altitude.
James Rohdes later noticed the Mark II after helping Tony prepare to fight against Iron Monger. Once Tony left Rohdes contemplated using the Mark II but opted against it and left promising to one day use it.
While dealing with palladium poisoning caused by his Arc Reactor and his impending death, Stark gave into his frustrations and got drunk during his birthday party, putting on his Mark IV armor and using it to show off in a reckless manner, endangering several of his party guests. Concerned over Stark's apparent irresponsibility and the safety of those present, James Rhodes donned the Mark II suit and confronted Stark, erupting into a brawl that caused massive property damage to Tony Stark's Mansion and nearly injured several guests.
After their fight reached a standoff, Stark and Rhodes fired their repulsors at one another, resulting in a repulsor explosion that destroyed a large portion of Stark's house. Rhodes, left standing over his dazed friend, then departed with the Mark II armor and he flew to Edwards Air Force Base, turning it over to the United States Armed Forces under his supervision.
The Mark II armor was a complete revamp of the base principle and technology of the rudimentary Mark I armor, using improved resources and new technology that Stark developed specifically for the suit. The original bulky design was considerably streamlined, giving the Mark II a sleek, more human-like appearance. In addition to the more articulated design, this suit also integrated a new user interface system based on Stark's J.A.R.V.I.S. AI.
The Mark II carried over the enhanced physical capabilities of the Mark I suit and enhanced them considerably, granting superhuman level strength, near bullet-proof durability, and enhanced movement speed and reflexes.
The greatest advancement for the Mark II armor was its vastly improved flight capabilities, now capable of sustained flight for long periods of time. This was made possible through Tony Stark's development of sustained flight thruster boots and hand based repulsor gauntlets for flight stability, all derived from and powered by his newly miniaturized arc reactor. The suit also possessed variable control surfaces for active flight control and maneuverability.
However, the Mark II appeared to lack any real form of weapons system, not yet possessing any of the Stark developed weapons that would later be integrated into future model of the armor. While its repulsors possessed an adequate amount of strength, they were developed solely for flight and not yet calibrated to be used specifically as weapons. They are still capable of firing repulsor blasts to a certain degree though.
It was discovered that the greatest weaknesses of the Mark II was its high altitude icing problem. Because the suit was still in the experimental stages, it was made of materials not tested for higher altitudes. Thus, when it was exposed to the thin, cold air of the upper atmosphere, a sizable layer of ice would form over its surface, immobilizing the suit and causing a complete system shut-down, proving nearly fatal for the user. Due to this, the Mark II was retired to make room for the Mark III, which was made out of materials specifically made for interstellar exploration. 
| Mark I • Mark II • Mark III • Mark IV • Mark V • Mark VI • Mark VII|
Mark VIII • Mark IX • Mark X • Mark XI • Mark XII • Mark XIII • Mark XIV • Mark XV • Mark XVI • Mark XVII •
Mark XVIII • Mark XIX • Mark XX • Mark XXI • Mark XXII • Mark XXIII • Mark XXIV • Mark XXV • Mark XXVI •
Mark XXVII • Mark XXVIII • Mark XXIX • Mark XXX • Mark XXXI • Mark XXXII • Mark XXXIII • Mark XXXIV •
Mark XXXV • Mark XXXVI • Mark XXXVII • Mark XXXVIII • Mark XXXIX • Mark XL • Mark XLI
Mark XLII • Mark XLIII • Mark XLIV/Veronica • Mark XLV • Mark XLVI
|Mark I • Mark II/Iron Patriot • Mark III|
|Mark I • Mark II|