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PREVAIL · BOXER BRIEF

4.9

Rated 4.9 out of 5 stars

4,622 Reviews

$37.00

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Select Your Color:

Ivory

Why You'll Love This

No seams, no lines, no distractions. A smooth waistband and four way stretch go anywhere.

VANGUARD

Say goodbye to waistband digs, underwear lines, and the friction distractions of your final mile ride.

SILVADUR™

SILVADUR™ antimicrobial delivers "intelligent" microbial control of bacteria that cause odor.

PRIME WICKING

AEROSKYN™'s 3D fiber network channels sweat and accelerates evaporation at core temperature.

MAXI-AIRFLOW

Airburst™ technology keeps you dry and cool, delivering the ultimate gear that eliminates discomfort.

Product Details

Designed for Peak Performance

Product Features

•Minimalist design
•Seamless leg openings
•Odor resistant
•Antibacterial
•Smooth 4-way stretch
•Moisture wicking finish
•Quick-drying
•Breathable design

Size & Fit Suggestions

•True to Size
•Snug, not tight
•Freedom of movement

Activities

•Basketball
•Casual Wear
•Running
•Cycling
•Strength Training
•Hiking

Material & Care

Materials

85% Polyamide (Nylon), 15% Lycra® Elastane
Certified Safe: OEKO-TEX® STANDARD 100 #HKKH 029897 by TESTEX

Care

Machine Wash Cold
Hang Dry

Best Pair Guarantee

If you're not satisfied with your first purchase, we'll make it right by issuing a refund or exchanging the item even if it has been worn. So If you've ordered multiple pairs of Aeroskyn™ on your first order, we suggest wearing one pair before opening the other pairs you've ordered.

4.9

Rated 4.9 out of 5 stars

Based on 4,622 reviews

Total 5 star reviews: 4.3k Total 4 star reviews: 207 Total 3 star reviews: 45 Total 2 star reviews: 11 Total 1 star reviews: 25

4,622 reviews

Sort

DR
Dmitri R.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF XS
I recommend this product
Rated 4 out of 5 stars
11/5/25
Works well for pickleball
Quick games stay dry and supportive.
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MZ
Miguel Z.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
11/3/25
Reliable for Long Runs
Finished a ten-kilometer run without any irritation or shifting. They hug just right, though I’d like a slightly lower waistband for easier breathing.
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FV
Francisco V.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
11/3/25
Breathable on Hot Nights
Wore them to sleep on a hot night. Very airy and comfortable.
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NP
Niko P.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/31/25
Bike ride approved
Ten-mile city ride with no chafing. Lightweight fabric kept me cool and the legs stayed put.
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VF
Victor F.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/28/25
Indoor lighting changes color
Color looks a bit different indoors than in natural light. Still very happy with the fit and breathability.
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U
UnderXLabs
10/30/25
Hi Victor F., we're happy you're satisfied with the fit and breathability! We've noted your feedback about the color variation in different lighting and will work on improving color accuracy.
FP
Felix P.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/27/25
Perfect for lounging
Honestly, I love wearing them just at home. Super breathable and never heavy.
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MN
Matthew N.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF S
I recommend this product
Rated 4 out of 5 stars
10/24/25
Great for Weightlifting
Stayed cool through my heavy lifting sets. I'd grab a few more pairs if there's a promotion.
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JT
Jack T.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF XS
I recommend this product
Rated 4 out of 5 stars
10/8/25
Everyday Comfort
These work well for both the job and traveling. They're a reliable pair I'd buy again.
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JN
Jared N.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
9/21/25
All-day comfort
Comfortable for a full workday. Thigh opening could be a bit more flexible.
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U
UnderXLabs
9/23/25
Hi Jared N., we're delighted they're comfortable for full workdays! We'll work on increasing thigh opening flexibility in coming iterations.
WF
Wyatt F.
Verified Buyer
Reviewing
PREVAIL · BOXER BRIEF XL
I recommend this product
Rated 4 out of 5 stars
9/18/25
No Lines All Day
Fits flat under dress pants and stays cool through long work hours.
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U
UnderXLabs
9/20/25
Hi Wyatt F., we're thrilled they fit flat under dress pants and stay cool through long work hours! That discreet comfort is ideal for professional settings.