Flash's Costume Ring is a small ring with a spring-loaded opening.
Barry Allen, the second Flash, used this ring to compress and conceal his costume while operating in his civilian identity. By thumbing a small stud on the side, the top of the ring opened, releasing the costume (chemically treated to shrink), allowing Barry the ability to change clothes at super-speed.
Wally West, the third Flash, also uses one of these rings, although he stopped for a long period of time, having learned to manifest a suit out of the Speed Force. Barry's grandson, Bart Allen, used a similar ring to hide his costume while he was the Flash, and another to house his Impulse and Kid Flash costumes (he does not remove this ring under any circumstances, at least not willingly).
The original costume ring was kept by Eobard Thawne, and would pass into the possession of Hunter Zolomon after Thawne's death. Hunter would use the suit after dubbing himself the new Flash 
- Bart's first costume ring, that in which he stored his Impulse costume, was a gift from Wally West, and a replica of Barry's original.
- Green Arrow used the ring given to him by Barry Allen as a gift when he proposed to his longtime girlfriend Black Canary.
- The Flash has shown the ability to vibrate and compress his molecules to actually hide himself inside of the ring when the situation calls for it.
- Appearances of Flash's Costume Ring
- Item Gallery: Flash's Costume Ring
- Images featuring Flash's Costume Ring
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