Several NFL players are bearing all for PETA’s latest “Ink Not Mink” campaign.

Buffalo Bills standout Shawne Merriman showed off his buff biceps in his recently released ad with the animal welfare organization. In the photo, shot by top photographer Tyler Jason, Merriman’s chest tattoo that reads "Heart of Gold" is visible.

According to PETA, despite being an organization for particularly rough sport, the NFL is not involved in practices that harm animals.

"Shawne Merriman is a tough opponent on the field, but it's as plain as the words on his chest that he has a heart of gold for animals," PETA Senior Vice President Lisa Lange said in a statement.

"Football's a rough sport, but as PETA's undercover videos show, it has nothing on the violence of the fur industry."

Upon the release of New York Jets Safety Bret Lockett’s ad, PETA clarified on Twitter that the NFL’s famous “pigskin” is actually made of synthetic materials.

“That NSFW! New England @Patriots' @BretLockett26 goes NUDE 4 @peta! And yes, football is SYNTHETIC leather #Obviously,” PETA tweeted.

The NFL player showed off a lot more than tattoos in his ad that released in late 2012.

Holding only a footfall in his photo, shot by top celebrity photographer Gabrielle Revere, Lockett advertises the campaign’s slogan "Ink, Not Mink. Be Comfortable in Your Own Skin, and Let Animals Keep Theirs."

Lockett also interviewed with PETA and revealed that he was encouraged to stop wearing fur after watching video footage of animals being killed for their pelts.  

"What really hurt me was when I saw that an animal was still able to move and lift its head up after it was completely skinned," Lockett said. "It brought tears to my eyes."

Merriman and Lockett are among many top athletes that have partnered with PETA, including Terrell Suggs, Willis McGahee, Chris Andersen, Chad Ochocinco, Amar'e Stoudemire, Tony Gonzalez, Aaron Curry, Michael Strahan, Gilbert Arenas, "Sugar" Shane Mosley, and Tito Ortiz.