The Steel Armor was developed by John Henry Irons first as a prototype that was designed to be used by the US Army. For whatever reason, it did not come to be as John would leave their services and take up the identity of Henry Johnson. Following Superman's death, however, John Henry would retrieve the mothballed armor and complete it, adding a S-Shield and red cape to it.
The original armor was incredibly durable, showing him shaking off shots from Toastmaster guns and allowing him to survive a fight with The Eradicator. It had jet-powered boots, enabling flight, increased his strength many times and was armed with a powerful nail gun and a large sledgehammer. However, the original armor was destroyed first when he succeeded in stopping Engine City from fully powering up then when Superboy was forced to use his Tactile Telekinesis to destroy the ravaged armor when the Cyborg Superman took control of it.
Irons would later develop various new armor, including one that exposed his face after he revealed his identity to the world. His current armor, though, is modeled after the original.
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