A hub was the shielding center for shockboxing armor. It was a diamond-shaped regulating device set in the center of the breastplate. Hubs powered the shockboxer's armor, in addition to providing readouts for scorekeepers and medics.
If an opponent was hit in the hub with an ion-charged shockmitt, the shield could be disabled. If disabled, it could cause an ion-out. Hits to the hub were known as hub-busters.