None, but wears a powered armor. Previously, during the 52 event John Henry Irons was altered by the Everyman Project and had become composed of stainless steel due to Lex Luthor tampering with John's DNA without John's consent. In 52 #29, the metal skin peeled off completely, leaving him again a normal human.
Living Stainless Steel (formerly): had a body composed of bulletproof stainless steel. In addition, he could generate enough heat to turn metal fluid (including his own body, which he could then drip off of himself in small amounts). It is as of yet unclear exactly how he generated the heat, though it might have been somewhat electric or kinetic in nature.
Genius-Level Intellect: Genius engineer and inventor. It is obvious that Dr. Irons possesses several degrees in Physics, Quantum Physics, Advanced Energy Physics, Temporal Mechanics, Mechanical Engineering, and Robotics. It is likely that he has even more education than can be currently assessed by the creation of his powered armor. Has knowledge of physics and ballistics.
Possesses the strength of a man that engages in intensive regular workouts. In armor, is capable of lifting 70 tons under optimal pressure
Electromagentic Pulses: The armor can be shut down through Electromagnetic Pulses
Steel Power Armor: Steel's powers vary in accordance with what hardware is currently available to him. He has modified the original weapons systems and suit several times since its debut and continues to refine its abilities. With his engineering, physics and ballistics knowledge, it is conceivable that the suit may potentially possess even greater power in the future. Currently it possesses the following abilities:
Superhuman Strength: Steel's powered armor increases his strength to the point of lifting 70 tons.
Immunity System: Steel has immune systems in his armor to help him fight off computer viruses. It takes about 30 seconds to get rid of the virus but after the 30 seconds he is free of it. With this ability, whatever computer system that gave him this virus, he will be able to fully control it when he's within a dozen feet of it. This system also protects him against physical mind control agents like Queen Bee's hypnotic pollen. The onboard computer can be attacked either with viruses or electromagnetic pheonomena that will temporarily override the suit's operation for 30 seconds while the system reboots. This reboot does not stop motor operations and Steel retains control of the armor unless the attack damages the boot level operation protocols which are separate from the operating system proper.
Computerized Communications and Scanning Array (CCSA): This technology is integral to the armor's technological advantages. The onboard computer comes equipped with high density, flash memory protocols for suit operation, including weapons management, power management, gyroscopic balancing, and analysis of electromagnetic phenomena. This analysis array is directed by a wave-emitter bound to the S logo and including weapons analysis and EM field analysis, remote program analysis, and rewriteable operating system protocols. Assumingly of Dr. Irons designs, it allows remote communication and reception of all normal radio, satellite and cellular communication bands. The armor can also receive signals on classified bands such as the Air Traffic Controller wavelengths and the NASA communication protocols. It can be supposed that the armor is also capable of communicating with the National Defense Commands of the United States as Dr. Irons clearance allows.
Radioscopic Scans: Able to analyze photonic energy given off from an object through readouts the armor gives.
Enhanced Durability: The suit's ability to impart a resistance to physical injury was quite considerable before the addition of the inertial dampening field. Small arms fire was generally not a threat but larger firearms could prove dangerous. All of the suits have performed admirably considering the opponents. These include the Cyborg Superman and Metallo.
Inertial Dampening Field: In his suit's most recent incarnation, he has opted to reduce the physical strength of the suit in exchange for an inertial dampening field. This field would increase his resistance to injury from physical attacks.
Jet Boots: With what are probably his greatest creations, the flight protocols for his armor are every engineers dream. The distance that can be traveled before refueling is unknown but Steel has made a documented trip of at least 1,500 miles before touching down again. It has been determined, by observation, that Steel can reach speeds just short of the speed of sound, which is 700+ miles per hour.
Rivet Cannon: This short range weapon has fired red-hot rivets similar to those used in construction.
Kinetic Hammer: His current hammer has the ability to increase it's kinetic energy the farther away it is thrown. At a distance up to 20 yards, it can stop a car, 30 yards, a truck, 60 yards, a tank, at distances greater than 60 yards, its destructive capacity rivals that of Superman for damage dealing capabilities.
Inertial Damage Field: This hammer can also store the energy it has gathered along its flight path within the kinetic field and release it on contact with a target (on command), even if its flight is interrupted by a command. It is unknown how long this device can store such energy. This device appears to have the ability to temporarily disrupt temporal/kinetic energy in a localized field and manipulate it for limited effects such as energy transfer based on a linear distance traveled. Such technology may be alien in origin and its owner and manufacturer bear watching because of it. Its power source is also unknown.
Programmable Flight: Can stop in mid-air and be called back into his hands.
Voice Controlled: When Steel says "STOP", the hammer will stop in mid-air. When he says "RETURN", the hammer will fly right back into his hands.
Electromagnetic Sensors: The hammer has sensors on it to measure electromagnetic energy.
Electromagnetism: The hammer can create several effects such as an EMP. It can also set itself in tune to the Earth's magnetic field, making it virtually impossible to move. When not using the hammer, he can magnetically attach it to his back.