Lingerie
Expertise
Why Underoutfit
Smoothing that disappears under everything
Our founders spent 30+ years designing for Victoria’s Secret, Nike, Spanx, Lululemon, Triumph, Maidenform and more. They built the 308 Brief to solve what no other underwear had — a waistband that smooths without digging, shapes without compressing, and disappears under any outfit.
Engineered to smooth and contour at the waist without any pressure, rolling, or digging into the skin — even after a full day of wear.
Ultra-thin seamless construction lies completely flat under fitted dresses, trousers, and activewear — invisible from every angle.
Soft, breathable fabric moves with your body from morning to night. Not shapewear — just underwear that happens to smooth beautifully.
Wear it, wash it, try it again. Return or exchange free for 180 days — we pay the shipping both ways.
Engineered for Comfort
Every Detail, Designed with Intention
Three decades of intimate apparel expertise went into every stitch. Here’s what makes the 308 Smoothing Brief different from anything you’ve worn before.
The Waistband That Holds Without Marking
Most waistbands do one of two things: dig in and leave marks, or sit loose and do nothing. Ours does neither.
The 2-ply waistband is engineered at the yarn level — not compressed onto your body, but knitted to sit flat and hold. No elastic bands. No hard edges. No red marks when you undress.
Second-Skin Feel. All-Day Breathability.
We don’t call this shapewear. That’s not an accident — traditional shapewear compresses. This fabric holds its shape around you, not against you.
The result is something most women describe the same way: you forget you’re wearing it. Your waist doesn’t.
Looks Small. Fits Perfect.
When you first hold this, it will look too small. This surprises almost everyone.
Put it on before you judge it. The unique yarn technology stretches and conforms to your exact shape — so what looks undersized in the package becomes a second skin once it’s on.
Still not sure? We encourage you to order two sizes and try both at home. Return or exchange the one that doesn’t fit — for free, for 180 days.
Customer Reviews
2,836 Women Can’t Be Wrong
“I’ve been searching for underwear that smooths without squeezing for years. This is it. The waistband sits perfectly, no rolling, no digging. I wear them every day and I’ve ordered six more pairs in different colors.”
“These are the most comfortable underwear I’ve ever owned. They’re not shapewear — they just make everything look smoother. I wore them under a fitted dress to a wedding and got so many compliments on how I looked.”
“I bought these with the matching bra and it’s the best set I’ve ever owned. The brief smooths my waist beautifully and I forget I’m wearing them. The 180-day guarantee meant I had nothing to lose trying them. Now I’m a customer for life.”
Join over 1 million women who have already made the switch.
Shop the 308 Smoothing BriefOur Story
Designed by the people who built the industry
Our founders spent 30+ years designing bras for Victoria’s Secret, Nike, Spanx, Lululemon, Triumph, Maidenform and more. They know what works — and they know what women actually want. Now they’re bringing that expertise directly to you.
Expert Craftsmanship
Every bra is the result of decades of intimate apparel engineering. Perfected fit for millions of women worldwide.
Women-First Design
Every detail is made for real bodies and real life. We design for how women actually live — not how they’re supposed to.
Trusted by 2M+ Women
Over one million customers have made Underoutfit their everyday essential. Join a community that knows what comfort really means.
“A bra to forget. — that’s not a tagline. It’s the standard we hold ourselves to every single day.”
Our Promise to You
180 Days to Fall in Love
We’re so confident you’ll love our garments that we give you 180 days to decide. Wear it, wash it, try it again. If it’s not right, return or exchange it — completely free.
- 1 Order your size — or try two sizes at once
- 2 Wear it, wash it, wear it again
- 3 Not right? Return or exchange — free, for 180 days
Wash & Wear · Free Returns · Free Exchanges