Rapper Paul Wall's Gold Grillz Giveaway To All U.S. Medal Winners!!

File Under: "Perks of Being a Winner" ... 'cause EVERY. SINGLE. AMERICAN ATHLETE who won a medal in Rio is being offered a FREE gold grill ... courtesy of rapper Paul Wall.

Wall and his partner, Johnny Dang, have been running a high-end grillz biz for years -- and want to reward our best athletes by blingin' out their mouths with a special Olympic-themed gold piece.

Dang tells TMZ Sports ... the offer is good for every single U.S. medal winner -- from Michael Phelps to Ryan Lochte to Katie Ledecky ... to the men's and women's basketball squads.

We're told the offer is for an "upper" piece made with 18k gold -- and the 2016 Olympics logo etched in the front.

By the way, according to our count ... more then 100 American athletes have earned medals so far.