Limiters

The Limiters (リミッター) are objects that appear in the Sonic X anime. They are rings worn by Shadow the Hedgehog to restrain his power which he has worn since his creation onboard the Space Colony ARK.

Description
The Limiters are golden rings that Shadow the Hedgehog wears on his wrists and ankles. When worn, they limit the amount of Chaos energy Shadow uses during combat and other situations. They also produce two red cuffs on his wrists for fixation. When he takes them off, Shadow can tap into his full strength, giving him a drastic boost in power, though at the risk of thoroughly over-exerting himself; in fact, without them, Shadow quickly tires out when fighting at just normal power.

The Limiters expand and contract to Shadow's will, allowing him to remove and put them on with more ease, although he can also remove them normally. The Limiter are connected to the red tongues on the black cuffs of Shadow's gloves; the red tongues disappear when the Limiters are removed, but regenerate when he puts them back on.

Shadow Saga
Seemingly given to Shadow the Hedgehog during his time on the Space Colony ARK, Shadow first removed his Limiters to boost his Chaos Control as Super Shadow so he and Super Sonic could sent the Space Colony ARK back into orbit. In the aftermath, Sonic could only find Shadow's Limiter which he gave to Chris who kept it as a memento of Shadow.

Metarex Saga
During the battles with the Metarex, Chris gave the Limiters back to Shadow so he would not lose consciousness in combat. Shadow would subsequently remove his Limiters several times to gain a power boost to combat enemy forces.

Trivia

 * When putting the limiters off, the Limiters light up with a transparent yellow aura in the Japanese version. However in the English version, the Limiters glow with a dark yellow.