HsPS-15

HsPS-15 (also called 'Large Weapon' (ラージウェポン)) is a technology developed by Academy City. It is the newest version of power armour as of Volume 14. It first made it's appearance in Railgun Anime Episode 12 cleaning up the the debris after the fight between Mikoto and the AIM Burst, and in the Vol.14 of the novels. It can be worn in addition to Anti-Skill's riot armor, but AI can also be programmed into the armour to make it work without a pilot. From Volume 14, Academy City are in possession of a few hundred of these, up to 1,000 in number.