The Boyshorts are soft, stretchy, and reduce friction between your thighs.
Customer Reviews
2,836+ Women Can’t Be Wrong
4.8
★★★★★
Verified Purchase
“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.”
★★★★★
Verified Purchase
“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.”
★★★★★
Verified Purchase
“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 Brief
30+
Years of
Lingerie
Expertise
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.
Smoothing Waistband — No Digging
Engineered to smooth and contour at the waist without any pressure, rolling, or digging into the skin — even after a full day of wear.
Seamless Under Any Outfit
Ultra-thin seamless construction lies completely flat under fitted dresses, trousers, and activewear — invisible from every angle.
All-Day Comfort, Every Day
Soft, breathable fabric moves with your body from morning to night. Not shapewear — just underwear that happens to smooth beautifully.
180-Day Risk-Free Trial
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.
01
The Mechanism
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.
2-ply construction — double layer at the waist gives smooth, even hold without a single pressure point
No hardware — zero elastic, wire, or rigid bands to cut in throughout the day
Tubular knit technology — the waistband isn’t sewn on. It’s knitted as one continuous piece, so it can’t roll or bunch
02
The Fabric
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.
No visible panty line — seamless finish sits flat under any outfit
Moisture-wicking — cooling fabric treatment keeps you fresh from morning to evening
Level 1 shaping — enough to smooth, never enough to restrict. Not for special occasions. For every day.
03
The Fit
Seamless Silhouette
No raised seams, no visible lines, no panty outline under clothes. The 308 disappears under everything — fitted dresses, tailored trousers, lightweight fabrics. You'll forget you're wearing it. Your clothes won't show that you are.
Runs true to size — if between sizes, size down for a smoother hold
Available S through 3X — inclusive sizing with the same fit experience across the range
308 Smoothing Brief
Built for Every Day —
Not Just the Days
That Need Shapewear
Most smoothing underwear is occasion-wear. You pull it out for events. You suffer through it. You take it off the moment you get home and swear you'll find something better.
The 308 Brief was designed for Tuesday. For the commute, the desk, the school pickup, the errand run, the dinner out. Wear it every day — wash it every night — and it holds its shape, wash after wash.
Monday
The commute.
7am to 10pm.
Tuesday
Back-to-back
meetings.
Wednesday
The errand run.
No adjusting.
Thursday
Dinner out.
Forgot it was on.
Friday
The long day.
Still there at 10pm.
20+ Colors
Match your undertones, coordinate your wardrobe, or just pick the one that makes you smile. Same fit experience across every color.
"S" Through "3X"
SmoothKnit fabric stretches more than it looks. Order your regular size. Unsure? Order two — return one free, no questions asked.
Wash After Wash
Same structure on wash 1 as wash 100. No elastic degradation. No shape loss over time. Machine washable.
Underwear you forget you own. That's the whole point. Not shapewear you endure — underwear that works so quietly you stop thinking about it entirely.
180-Day Trial↩
We let you wear it,
wash it, and still return it.
We offer a 180-day free return and exchange policy. Not because we have to — because we know what happens once you actually feel the difference.
Wear it. Wash it. Live in it. If it's not the most comfortable underwear you've ever owned after 180 days, we'll take it back. No questions, no restocking fees.
We can afford to do this because the return rate is low. Women don't send these back.
180
Days to try at home. Worn and washed.
Free
Returns and exchanges. No questions asked.
4.8★
Average across 2,698 verified reviews.
Press & Media
As Seen In
So comfy you forget you’re wearing them.
The Bra is a feminine, comfortable bra that enhances your natural shape.
So many reviewers are calling it their “new favorite bra.”
Very few brands offer such a long period for returns or exchanges.
Our 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.”
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