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PREVAIL · LONG BOXER BRIEF

4.9

Rated 4.9 out of 5 stars

2,563 Reviews

$42.00

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Rock

PREVAIL · LONG BOXER BRIEF

$42.00

(4.9)

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 2,563 reviews

Total 5 star reviews: 2.4k Total 4 star reviews: 106 Total 3 star reviews: 25 Total 2 star reviews: 7 Total 1 star reviews: 14

2,563 reviews

Sort

EG
Ethan G.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/29/25
Great for Hiking
Hiked steep trails and felt supported. Would stock up with a discount.
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AM
Austin M.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/13/25
Breathable Gym Gear
Used them for weight training and a short run – they stay cool, wick sweat effectively, and fit well without riding up. I'd buy more if there's a good promotion.
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AO
Ali O.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/10/25
Pilates Evening Class
Wore them for evening Pilates with lots of core work and twisting. Super comfy and breathable. Felt a little snug around the hips after an hour, but still great.
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JT
Jacob T.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
10/8/25
Works for lacrosse games
Evening scrimmage in humid conditions – no chafing and solid breathability. Would prefer the waistband sit a bit lower during sprints, but still performed well.
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AW
Ali W.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
9/5/25
A workout essential
Great as a base for weightlifting or running, zero lines under shorts.
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RT
Reed T.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
Rated 3 out of 5 stars
7/31/25
Tardy But Worth It
Late by 2 days from the estimate, but to be fair, so am I to most things. The underwear fits great at least!
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U
UnderXLabs
8/2/25
Hi Reed, thank you for your review of our underwears. We deeply appreciate your feedback. We're thrilled you found the fit great, but we're sorry the delivery was tardy. We'll share this with our team to improve shipping timelines. We're committed to enhancing our service to ensure prompt delivery.
AM
Anders M.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF M
I recommend this product
Rated 4 out of 5 stars
7/24/25
Good even after shipping delay
Package came in about ten days. Fit is excellent and the fabric dries fast after workouts. Worth a little wait.
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U
UnderXLabs
7/26/25
Hi Anders M., we're happy they arrived and that the excellent fit and fast-drying fabric made the wait worthwhile! Thank you for your patience and support.
ZA
Zev A.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF S
Rated 3 out of 5 stars
7/22/25
Protective Packaging Win
Outer box was damaged in transit, but the inner product packaging did its job perfectly. Zero effect on the actual underwear quality.
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U
UnderXLabs
7/24/25
Hi Zev, thank you for sharing your thoughts on our underwears. Your perspective is greatly valued. We're sorry the outer box was damaged, but we're glad the inner packaging protected the product. We'll share this to improve outer packaging durability. We're committed to enhancing our service for flawless deliveries.
PD
Patrick D.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF L
I recommend this product
Rated 4 out of 5 stars
7/21/25
Reliable running partner
Perfect for short runs. They breathe well and don't shift around, even when you work up a sweat.
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LW
Lucas W.
Verified Buyer
Reviewing
PREVAIL · LONG BOXER BRIEF XXL
I recommend this product
Rated 4 out of 5 stars
7/20/25
No-Adjustment Needed
Held up well through a 5K run and meetings without needing to pull or adjust.
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