The stunning doorbell footage of Nancy Guthrie’s ᴀssumed kidnapper reveals crucial information about the masked suspect, including key physical and behavioral traits that could help authorities identify him, according to a body language expert.

The previously unreleased Google Nest camera pH๏τos and video released by authorities on Tuesday — 10 days after Guthrie is ᴀssumed to have been abducted and held for ransom — shows a man in a ski mask armed with a gun outside the 84-year-old grandma’s Tucson home.

Even though the mask hides most of his face, his dark-colored eyes, jawline, height, physique and gait are all identifiable, body-language expert Susan Constantine told The Post.

“Everybody is designed differently. We have our own body language, DNA, how we walk, and whether you’re pigeon-toed or whether you’re bow-legged or what, one foot, that kind of goes out further than the other one,” she said.

“These are characteristics because when they do find a person of interest, these are the things they can measure them by.”

Constantine said the man appeared to have a beard underneath his mask, which he could easily shave off.

“But you can’t change his height, his body structure … his shoe size.” she said, noting he appears to be about 5’10” or 5’11” and in “physically good shape.”

The suspect’s head shape and lack of visible hair also suggest the man could be bald, she told Fox News in a separate interview.

The expert also noted the suspect had a backpack that appeared full — potentially showing he was well-prepared for the kidnapping.

He seemed to have a flashlight in his mouth as he fumbled with the camera, at one point grabbing nearby flowers and placing them in front of the lens.

There’s “no signs of anxiety,” Constantine said.

The black-and-white footage, which appears to show the suspect tampering with the camera the morning Guthrie vanished, shows a man who seems physically fit, with brown eyes and olive-toned skin, Constantine said.