It didn’t look like much on the hanger — a cross between a mechanic’s uniform and a stiff tarp.

But something amazing happened when I put it on.

The unpromising, boxy breast pockets were strangely flattering.

The canvas belt hugged my waist perfectly. I was no longer a deskbound, denim-clad writer — I was a street-style star, ready to strut down the block with a trail of photographers in my wake.

In short, I felt quite glamorous.

The boiler suit, or coverall — a long-sleeved one-piece garment made from heavy fabric, such as thick cotton or canvas — is the unlikely breakout trend of the season.

Once a turn-of-the-century sack meant to protect a laborer’s street clothes from muck, it’s now considered a chic fashion statement.

Luxe labels from Comme des Garçons to Emporio Armani have embraced the look, and the likes of Victoria Beckham, Kaia Gerber and Rihanna are stepping out in full-boil.

The eye-catching style is so popular that hip boutique Bird Brooklyn stocks six different versions, says Christopher Yang, sales associate at the Williamsburg outpost.

Jessy Cain, a stylist who works with stars such as Christina Aguilera and Miley Cyrus, explains why coveralls are suddenly coveted.

“It’s a fun piece of clothing,” says Cain, who recently dressed Aguilera in Orseund Iris’ version for a casual-cool daytime Beats 1 Radio appearance. “It’s versatile, super easy to wear and looks good on almost everyone.”

New Los Angeles-based brand Lincoln is counting on the boiler suit’s broad appeal.

Launched in September, the stylish startup sells just one $250 cotton suit in six colors.

Co-founder Katie Hatch, who based her roomy unisex design on a $20, unlabeled piece she discovered a few years ago at a Massachusetts antiques market, says she’s offering her customers a unique — and of-the-moment — wardrobe solution.

“It’s an update to that one-piece outfit that used to be the dress for women,” Hatch says. “But with the pockets and freedom of movement, this is so much more functional.”

I must say, I agree.

Wearing the boiler suit, I felt surprisingly tough.

The heavy cotton fabric enveloped me like armor.

I liked how I looked, and I wasn’t thinking about my body.

Worries of a wardrobe malfunction — an errant bra strap, a muffin top, visible panty lines — were delightfully far from my mind.

Just call me Rachelle the Riveter. I’ve found a new go-to for fall.

Photos: Tamara Beckwith/NY Post; Stylist: Nicole Zane; Hair/Makeup: T. Cooper/crowdMGMT using ECRU New York