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Everyday Series

Crossfly Men's Trunks - IKON X 3"

Fit tips

We recommend you go down a size in this style if you sit in-between sizes to get a more contoured fit as the modal fabric is very stretchy. (Ie: if normally a S/M or 31-32", please opt for S)

Size: S What's your size?
Size Guide

Men's Underwear

underwear size guide

The measurements on the size chart are body measurements. Find your correct size in the chart below.

Note that each style may fit differently due to the fabric used.

Size Chart








Waist (Inch)







Waist (cm)








Fit Tips

IKON & IKON X styles: (Choose one size smaller)

This style is made from Modal fabric which is quite stretchy. As such, we recommend that you order one size smaller than your usual size for a better fit.

PRO 7" style: (True to size)

Our customers find this style fits true to size.


How to measure

  • WAIST: Measure around the narrowest part (typically where your body bends side to side), keeping the tape horizontal.
  • INSEAM: Measure the from where your crotch meets the top of your inner leg.
Crossfly-how to measure
Color: Black/Silver
  • First Pair Money Back Guarantee


Our game-changing Everyday Series is the ultimate premium underwear, combining two patent-pending technologies. The innovative X-Fly provides fast and easy access, and our Coccoon internal support system minimizes chafing and provides optimal comfort and support. Teamed with our super-soft Modal fabric, we are confident Crossfly will soon become your everyday go-to favourites.

  • 95% modal / 5% elastane
  • Super soft fabric for next-to-skin comfort that dries fast and remains breathable

Arguably the best & most technical pair of underwear man has ever seen, the IKON X 3" is loved by our customers for being the most comfortable pair they've ever worn with features that make sense and work.


    Eliminates skin on skin friction and chafing providing greater comfort and support.

  • X-FLY

    Easier, faster access when nature calls.

  • ZEROFOLD 360

    Stays in place however active you are. 4-way stretch construction works with your every movement.

  • DRI-PX2

    ‘No Show’ Dual layer protects against excess drips and moisture.

This boxer is made from Modal fabric which is naturally quite stretchy. As such, we recommend that you order one size smaller than your usual size for a better fit. This 6-inch inseam style is a mid-rise which means they’ll sit on your hips nicely for a classic look. Not too high, not too low.
The guy who goes between the gym and the boardroom. This versatile pair is designed for a wide range of sports from running to hiking as well as more relaxed activities.

Customer Reviews

Based on 72 reviews
Ian Dalzell
Top quality

Ordered a pair a few months ago to try them and was blown away by how comfortable and well fitted they were. A few months later and I've ordered a two more pairs. Crossfly will eventually replace all other underwear i have.
The price can possibly put some people off but Crossfly will not disappoint.

Martin Walton
Satisfied repeat customer

Very pleased with the quality and fit of these Icon X 3" Trunks and ordered a further supply as a result. Happy to recommend.

Brain Lilley
New favourite pants

Super comfy trunks and the crossfly access is great, no more fishing around. 👍

Mark Iles
Like the Design, Love the Feel!

Super soft and comfortable fitting. Supportive pouch keeps the boys cool. Waistband like not even there it’s so comfortable.

David Cates
Comfy, but doesn't support all day

Wore it at work to try it, pretty comfy but doesn't have the pouch support that I thought it did. Kept having to "adjust". I'll keep for weekends though.

Hi David, many thanks for writing a review. We're sorry to hear you haven't experienced the support from the Coccoon internal pocket. May I check that you are happy with the size purchased? The IKON style fits more loosely than the Pro 7' boxer due to the very stretchy modal material so this could be the reason. Please do not hesitate to get in touch if there's any way we can help! Very best, Val & Crossfly team


Good so far, the design is fine. Waiting to see how the trunks survive washing.

Money back guarantee

Love them, or we'll refund or exchange your first order.

"Arrived on Saturday and I can honestly say that they are worth every penny"

- Vince Harris

Crossfly has been a vision of a small team of sporting product professionals from the UK and America. Together, we have acquired decades of experience working in the Sports industry for global brands within Marketing and Product Innovation. After a few false starts, some legal issues, a eureka moment, and a global Pandemic Crossfly was finally ready to get going.

WE'VE RAISED THE BAR and deliver the most comfortable underwear and socks you will ever wear; packed with patent pending technologies and features that offer ultimate comfort whatever you're doing. GAME. CHANGED.