Auto Balancers

The Auto Balancers are support equipment designed and assembled by Mei Hatsume, a student in U.A.'s Department of Support. The rig makes its name during her Sports Festival bout with Tenya Ida, who wore it for the duration of the fight. It first appears in Chapter 35 of the manga and Episode 21 of the anime.

The apparatus splits across two locations on the body. One component straps to the legs, the other mounts on the back, and the two operate together to hold the wearer steady through fast, unstable movement.

The lower half resembles a set of braces, though bracing is not what it does. It assists the wearer's stride instead, cutting the effort a run demands until the legs feel considerably lighter than they are. The upper half is built around a pair of aileron-like fins, with three cylinders suspended beneath each one. Those cylinders are what let a runner hold a line and cut sharply into a new direction mid-race.

Prediction is the trick behind the responsiveness. The leg units pick up the wearer's brainwaves, anticipate the next motion, and answer almost instantly with no perceptible delay. A 32-axis gyro sensor rounds out the system: the moment it registers a fall in progress, the cylinders vent air and shove the user back into position. Short of the wearer deliberately choosing to go down, the gear will not let them hit the ground.

Mei Hatsume created the Auto Balancers and owns them, but Tenya Ida is the only person seen wearing the set, and only on a temporary basis during his Sports Festival match against her.