Trunk Size Chart

Fit Profile: True to Size

Trunk Size Chart
Size: S M L XL XXL
Waist: 28-30" 31-34" 35-39" 40-43" 43-46"
Outseam: 6-7" 7-8" 8-10" 10-11" 11.5"

  *Standard Trunk Size Guide Measurements:

Waist: Circumference measurement of waist. Trunks are designed to fit above the hips.

OutseamMeasure the length from the intersection of the waistband & hip to the bottom hem, follow the outer seam.

*Product measurements can vary by 1/2" 

Your purchase includes our "Love Your Fit" guarantee

If you don't love the fit, send it back and we'll exchange the size so you're happy.

 

Sale

Flex Trunk - (FINAL SALE)

149 reviews
Sale

Flex Trunk - (FINAL SALE)

149 reviews

Designed with increased compression, breathability, and support for your more intense days. Learn More

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Flex Trunk ">
Description
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Flex Trunk ">

The Flex Trunks were designed for your more intense days. This custom blend has increased compression, breathability and support. It also features cooling mesh zones for anti-odor and temperature control.

The Flex Trunk
Polyester 84% POLYESTER
Spandex 16% SPANDEX
Flex Trunk
Breathable BREATHABLE
Anti-Odor ANTI-ODOR
The BYLT Difference
Style, performance & comfort are our design principles that we use in creating our entire line.
Our Guarantee
It is critical to us that you are happy with your purchase and that you love the items you receive. We know things happen, if you are not 100% satisfied, we will try our hardest to make it right.
Experience Premium
We're here to upgrade your basics. Every BYLT product is rigorously tested before it's shown to the world to ensure it is nothing less than premium.
Customer Reviews
4.8 Based on 149 reviews
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  • boxer briefs
04/11/2017

Flex Boxer Briefs Live up to Hype

Dale H.

Excellent compression fit on legs but because I'm on the line for size I'd order up one size next time. Additional colors would be great!

07/18/2020

Best briefs ever?

Eric G.

Definitely the best boxer briefs I’ve had. So much that I have one for everyday of the week, even two extra for laundry days.

05/25/2020

Great underwear

Alex R.

Fits good, never purchased underwear like this. I don’t like briefs and tight underwear in general but these are “fitted” and give your boys some breathing room. Plus girlfriend definitely approves

05/17/2020

Amazing Brand

Edgar M.

Great Quality!

05/12/2020

Perfect fit

Daniel G.

Fit perfect and the girlfriend loved them on me

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Our Signature Fabrics

BYLT Blend™ Fabric

Premium signature blend of Cotton, Polyester, and Spandex. Perfect for your essential everyday shirt, leaving you with that flawless BYLT Fit.

LUX Blend™ Fabric

High-quality performance blend of Cotton, Polyester, and Spandex. Reactive fabric allows for slight reduction in length to provide the perfect structured fit.

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Trunk Size Chart

Fit Profile: True to Size

Trunk Size Chart
Size: S M L XL XXL
Waist: 28-30" 31-34" 35-39" 40-43" 43-46"
Outseam: 6-7" 7-8" 8-10" 10-11" 11.5"

  *Standard Trunk Size Guide Measurements:

Waist: Circumference measurement of waist. Trunks are designed to fit above the hips.

OutseamMeasure the length from the intersection of the waistband & hip to the bottom hem, follow the outer seam.

*Product measurements can vary by 1/2" 

Your purchase includes our "Love Your Fit" guarantee

If you don't love the fit, send it back and we'll exchange the size so you're happy.