Executed by performing a half-circle backward motion and pressing kick, the user lunges forward while attempting to grab the opponent; if successful, he grapples the opponent's shoulders and flips over them, landing on the far side. Immediately afterward, there is a split-second time window for the user to follow up with an attack or combo before the enemy has a chance to strike back.
Both EX Special versions can grab the opponent at a further distance, and have faster execution and a slightly longer window of vulnerability for attack right after landing.
Fei Long gains a similar move called the Tenshin in the Street Fighter IV series. Chun-Li also possess a functionally (and visually) identical move in SVC Chaos: SNK vs. Capcom, the only game where she has such a move.
The move does no damage at all (except in Ultra Street Fighter IV, where it inflicts one point of damage, which in turn scales the following hits), being used mostly to disorient the opponent. Particularly in 3rd Strike, any Super Arts that connect right after this move have their damage somehow scaled.