One small step for Playboy, one giant leap for mankind.

Tomorrow during a photo shoot in Chicago, Jennifer Krum – a 25-year-old amputee model who lost her left hand and forearm in a car accident when she was 4 – will take it all off for a Playboy.com pictorial.

“If I was an able-bodied, all-of-my-limbs girl, I don’t know if I’d do it,” Krum confessed to Lowdown yesterday. “I’m doing it mainly because I want to send the message to people who are amputees, or have issues with confidence or don’t find themselves attractive or sexy – that you can be attractive or sexy, even if you’re an amputee.”

Krum, who lives in Pennsylvania, was discovered by Hugh Hefner’s venerable mag after she won Howard Stern’s “Miss Amputee 2004” contest last week.

“They heard the broadcast and called Howard after they saw my pictures online. It says a lot about Playboy,” she added. “They’re sending a huge, positive message. They’re saying they don’t mind. It’s a completely awesome thing around for everyone involved.”

Yesterday, Playboy.com’s editor in chief, John D. Thomas, told Lowdown: “She’s a very attractive woman. We would not be taking the pictures if she weren’t.

“Is it provocative? Duh. Of course. There are people who might think it’s too offbeat, odd or disturbing. But I think that there are a lot of people out there who are in a similar position as she is who will say, ‘Hell yeah’ or ‘Damn right.’ ”

He continued: “There’s no jokey aspect. There’s no wink-wink, nudge on our end. I don’t know what kind of stigmas she has associated with being an amputee, but this will be one of the most affirming, positive experiences of her entire life.”