For more background information about the T-51b and its appearances in other games, see T-51b power armor. For an overview of various models of power armor in the Fallout series of games, see Power armor.
A suit of T-51b power armor. The hardening process has improved the defensive capability of this high-tech armor system.
A suit of T-51b power armor (which has undergone a special chemical hardening process). The nature of this process is unknown, but the result is greater resistance to all forms of damage. A hardened suit retains the original's bonuses: +3 Strength and +30 Radiation Resistance.