London, Kelly boast appealing relatability

It takes guts to open your closet doors to co-hosts Stacy London and Clinton Kelly of TLC’s “What Not to Wear.”

“They are like your brutally honest best friend,” says TLC senior VP of production and development Nancy Daniels.

Each week, London and Kelly cringe and quip their way through renovating a real woman’s wardrobe, tossing in catchphrases like London’s famous “Shut up!” (Translation: I love your outfit!)

The critical-but-constructive tone has helped “WNTW” reach a milestone 250th episode since premiering on TLC in 2003, and has turned London and Kelly into brands.

Like media stars Oprah, Martha and Rachael, the duo have become so identified with a certain point of view that companies knock on their dressing-room doors for endorsements.

London does commercials for Pantene, Woolite, Lee Jeans and Dr. Scholl’s. Kelly does style seminars for Macy’s called “Makeover America” and reports strong sales of his lifestyle how-to book “Freakin’ Fabulous.” Both get approached at malls and restaurants by fans asking, “What do you think of my outfit?”

Perhaps ironically, London and Kelly didn’t see themselves as fashion insiders — despite the fact that London started her career at Vogue and other fashion mags, while Kelly was a former fashion magazine editor.

“All of the time I was in fashion editorial, I felt like an outsider,” London says. “I’m not 6 feet tall. I’m not 100 pounds.”

Kelly almost walked out of his “WNTW” audition.

“I’m so not a fashionista. I’m not on pins and needles until the next Balenciaga show,” he says.

In other words, they’re no Heidi Klum and Tim Gunn. Instead, in marketing lingo, they’re “relatable.”

They come across as ordinary people with jobs and lives who work with ordinary people who have jobs and lives. They build trust and brand identity by doing projects outside the show that echo the “WNTW” focus on real women — like Kelly’s next undertaking: a clothing line for QVC, using a size 14 model.

They also don’t say “yes” to every endorsement request.

“I only work with companies I already use,” says London, who does not color her streak of gray hair. “I’m not interested in representing diet food. I look for products that enhance the style process, not make you feel like you have to conform to a standard of beauty.”

Working together as a pair has helped hone their brand identities as well.

“They soften each other,” says Allison Wallach, “WNTW” executive producer and senior VP of programming at BBC Worldwide Prods.

Teamwork has also boosted the profile of “WNTW” makeup artist Carmindy.

“Women come off being constructively criticized by Stacy and Clinton, and they land with Carmindy,” says Wallach, who credits Carmindy’s purely positive identity on the show as one reason she has her own line of makeup with Sally Hansen.

Being a brand has drawbacks. London says her Twitter followers tweet, “Can you hock anything else?” Adds Kelly, “I’ll say, ‘It doesn’t really fit with my brand,’ and I think, ‘Did that really come out of my mouth?’ “

But London sees her work as a mission.

“Imagine if everyone felt just incrementally better about themselves,” she says. “It would change the world.”

There’s no end in sight to saving humanity through better shoes. “WNTW” gets between 5,000 and 7,000 makeover requests per month. And the series will tackle them with a new brand onboard: This season, hairstyle guru Ted Gibson has replaced Nick Arrojo.

“It was a way to bring in a new audience, not just a TV audience but a fashion audience,” says London.

But can a guy who does $900 haircuts be as relatable as London and Kelly? He’s off to a good start. His product line isn’t in Bendel’s — it’s in Target.

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