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PREVAIL · TRUNK

4.8

Rated 4.8 out of 5 stars

2,797 Reviews

$37.00

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Select Your Color:

Glacier

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

Engineered for 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

You have 30 days to try your first pair. If it is not right for you, we will refund or exchange it, even after wear. Start with one pair and take it through real training and real days. If your first order includes multiple pairs, try one before opening the rest.

4.8

Rated 4.8 out of 5 stars

Based on 2,797 reviews

Total 5 star reviews: 2.5k Total 4 star reviews: 211 Total 3 star reviews: 43 Total 2 star reviews: 13 Total 1 star reviews: 28

2,797 reviews

Sort

RS
Raj S.
Verified Buyer
Reviewing
PREVAIL · TRUNK XL
I recommend this product
Rated 4 out of 5 stars
11/5/25
Pickleball Morning Rally
Played several morning pickleball matches. Supportive and dry all session. The hips felt slightly snug after repeated lunges, but still very comfortable.
Was this helpful?
JL
James L.
Verified Buyer
Reviewing
PREVAIL · TRUNK XS
I recommend this product
Rated 4 out of 5 stars
11/4/25
Handles tropical heat
Vacationed in Hawaii with these - the lightweight material handled humidity like a champ. Didn't get that damp, clingy feeling even after hours outdoors.
Was this helpful?
LG
Leon G.
Verified Buyer
Reviewing
PREVAIL · TRUNK S
I recommend this product
Rated 4 out of 5 stars
11/4/25
Weekend Getaway Pick
Quick-drying and comfortable for short trips and varied activities.
Was this helpful?
U
UnderXLabs
11/6/25
Hi Leon G., we're happy they're quick-drying and comfortable for short trips and varied activities! That versatile performance is perfect for your active lifestyle.
EB
Erik B.
Verified Buyer
Reviewing
PREVAIL · TRUNK S
I recommend this product
Rated 4 out of 5 stars
11/2/25
Nice Everyday Wear
Feels fine for long walks or just relaxing at home. Not amazing, but worth keeping in the drawer.
Was this helpful?
U
UnderXLabs
11/4/25
Hi Erik B., we're glad they work well for walks and relaxing at home! We appreciate your honest feedback and are happy they earned a place in your drawer.
JV
Jonathan V.
Verified Buyer
Reviewing
PREVAIL · TRUNK M
I recommend this product
Rated 4 out of 5 stars
10/30/25
Daily Go-To
My grab-and-go pair for everyday wear.
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FK
Felix K.
Verified Buyer
Reviewing
PREVAIL · TRUNK XL
I recommend this product
Rated 4 out of 5 stars
10/13/25
Easy Choice
Simple design, good fit, does the job.
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AX
Amir X.
Verified Buyer
Reviewing
PREVAIL · TRUNK M
I recommend this product
Rated 4 out of 5 stars
10/2/25
Cool and supportive
Great for pickup basketball and weekend hikes. Light, breathable, and they keep everything in place. I’d happily buy a few more if there were a multi-pack deal.
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EM
Ethan M.
Verified Buyer
Reviewing
PREVAIL · TRUNK XS
I recommend this product
Rated 4 out of 5 stars
10/2/25
Hiking Comfort
No chafing on a long trail. Fabric’s a bit thicker than I expected.
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EL
Enzo L.
Verified Buyer
Reviewing
PREVAIL · TRUNK M
I recommend this product
Rated 4 out of 5 stars
9/29/25
Outdoor Climbing Trip
Spent half a day on outdoor climbing routes. These stayed cool even under the harness. After many climbs the leg openings felt a bit tight, but nothing serious.
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TJ
Thomas J.
Verified Buyer
Reviewing
PREVAIL · TRUNK M
I recommend this product
Rated 4 out of 5 stars
9/20/25
Office sharp
Invisible under tailored pants, breathable for long meetings.
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U
UnderXLabs
9/22/25
Hi Thomas J., we're happy they're invisible under tailored pants and breathable for long meetings! That professional comfort is ideal.