The annual Miss USA concert will be premiering on NBC on June 16 at 9 p.m. ET, but before the show is held, a few of its past winners have dropped their swimsuits and ball gowns for animal rights. What better reason to get naked than for an important cause?

Four gorgeous pageant winners from previous competitions are posing nude in the sexy black and white ad. Shanna Moakler (1995), Shandi Finnessey (2004), Susie Castillo (2003) and Alyssa Campanella (2011) stripped down for their beliefs in the new PETA (People for the Ethical Treatment of Animals) advertisement.

But the girls do cover up their unmentionables as they stand side by side with the words "Feel Beautiful in Your Own Skin, and Let Animals Keep Theirs” underneath them. Moakler, Finnessey, Castillo and Campanella have united with the animal rights campaign to urge the pageant industry in general to frown upon using fur in pageants nationwide, according to The lovely ladies are also requesting that the state pageants stop giving out fur coats as prizes to winners, considering some competitions still do so.

"As long as I'm the director of Miss Nevada, we will never award fur coats as prizes, and I urge my fellow pageant directors to make the same pledge," Moakler said in a statement to PETA that's quoted by the celebrity news site. "Kind people today are taking a stand against cruelty to animals -- so a fur coat is no prize for a compassionate, socially-aware woman."

"I've been an animal lover all my life, and the more I learned of the torture that animals go through in the name of fashion, I just think it's so unnecessary," Castillo said in her statement. She added that she felt honored "to take a stand united and to tell the pageant industry not to support the fur industry."

Check out the behind the scenes video below: