as well as a personal reminder of his origin.
The Flash is a unique character in that he has two debut issues. The original Flash, Jay Garrick, made his first appearance in Flash Comics #1 in 1940. A college student who acquired his super-speed powers through inhaling hard water vapors (simply water with a high mineral content), Garrick's popularity waned after the conclusion of World War II along with many other superheroes. The second Flash debuted in 1956's Showcase #4, in which scientist Barry Allen was struck by lightning after being bathed in unknown chemicals. He developed similar powers, but unlike Jay Garrick, Barry had a unique method of donning his costume: the Flash ring.
After discovering his abilities and saving his girlfriend Iris from the Turtle Man - the so-called Slowest Man on Earth - Barry decides to become the Fastest Man on Earth and subsequently creates a costume for himself. Inspired by the Golden Age Flash (a comic book in this universe), Allen coats the costume in a chemical solution that "...swell[s] the costume to life-size...just like the rubber rafts tossed out by Navy planes when crash-landing!" Silver-Age comics had a tendency to explain their more fantastical elements with real-world technology (see early Iron Man and his fascination with transistors), but the author made a small error: the rafts in question inflate via a chemical reaction, not expand. Unless Flash's costume is double-layered and made of rubber, the explanation doesn't hold water.
The ring's functionality would be further detailed in later issues; it can suck the suit back inside itself via a special emitted gas and flings the suit out of the ring with the force of nine airbags. Barry puts the suit on via super-speed as the ring opens, ensuring that no one else but him (and other speedsters) can wear it. In The Flash Vol. 4 #0 in 2012, the mechanics of the suit's properties were changed. Using the Speed Force, Barry creates a thermal expansion that allows the suit to grow and shrink at the will of the wearer. Furthermore, the suit is stored in pieces within the ring and comes together through the Speed Force.
Barry's ring also carries sentimental value, at least from the New 52 era and beyond: the ring's band is forged from the wedding rings of his mother and father. It serves as a reminder of why he became the Flash in the first place: to save lives and protect the innocent, even at great risk to himself. It's a quiet personal touch to what is otherwise a loud and visible hero with an equally visible set of powers, and makes Barry Allen's ring a character element in its own right.
