EXCLUSIVE: Chrissy Teigen Talks Posing Nude in ET's Dressing Room, Offers to Auction Chair Off for Charity

The model tells ET that she'd sign the chair for charity in a "heartbeat."

Chrissy Teigen used ET's dressing room in New York City as the location for a pretty sexy photo shoot.

The 31-year-old model posted a pic to Instagram on Thursday afternoon of her posing nude in a chair following her interview with ET about the 2017 Sports Illustrated Swimsuit issue. "Just a typical press day with @mj_day for the launch of @si_swimsuit 2017!!" she captioned the image.

That evening, ET caught up with Tiegen again at the SI Swimsuit party in NYC, and she joked about getting naked in our dressing room. When asked if she would sign the chair she posed in and auction it off for charity, she exclaimed, "I would do that in a heartbeat."

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"Anything for charity, hello," she continued. "I'll sign in a heartbeat. You should have brought it."

Teigen also shared her secret to striking the perfect pose when nude, or when modeling for SI. "I love to lay on my side. That's my favorite because I'm lazy," she quipped. "I'm the first to be like, 'Let's do one like this,' and I lay down on my side and then I pop my butt. I feel good that way. I love it."

However, Teigen added that her technique might not work for everyone. "I just think everybody is so incredibly different and we all have different body types and what works for my body doesn't work for the next person," she explained. "I truly do the best I can do for my body because I know that I'm not gonna ever have those curves and that a** and that waistline. That's just not my body and I'm fine with that. I really am."

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Reporting by Darla Murray.