Is the name of a younger sidekick to The Flash. Once use by Bart, saying he will never be Kid Flash, he took the name Impulse because of his impulsive behavior.
Iris took the name after she became a full speedster. Surprising everyone including her Dad and Bart.
Iris West- (Impulse II) Took the mantle of Impulse.
Bart Allen- (Impulse) Did not really act like a sidekick as Impulse. Redirect kid flash