A lighter and stronger take on underwear, we created the fabric with plenty of nylon for strength, modal for softness, spandex for stretch, and SilverAir yarns for odor resistance. The knit structure of the fabric is open and breathable, and works very differently than our Merino Wool Underwear. Instead of pulling moisture into the core, it wicks it away. While the anti odor performance will not be as effective as our merino products, it dries faster and can be washed and ready to wear within a few hours. This product does not feature the SmartGrip System found in our Merino Wool underwear; otherwise, the construction and components are identical.


SilverAir Ultralight Boxer Brief w/Fly
Carbon Black
Carbon Black
Carbon Black
Carbon Black
Stone Grey
Stone Grey
Stone Grey
Stone Grey
Polar White
Polar White
Polar White
Polar White

Boxer Brief w/Fly

40 Reviews

$ 28.00

  • Polar White
  • Stone Grey
  • Carbon Black
  • S
  • M
  • L
  • XL
  • XXL
    • Lightweight open-knit fabric dries quickly
    • SilverAir Technology reduces odor
    • Double soft waistband doesn't roll over or leave marks
    • 50% Nylon, 35% Modal, 10% Spandex, 5% Metallic
    • Manufactured in China


(based on body measurement in inches)


We want you to love your gear and offer a try-on guarantee for your first pair of underwear. If you don't love it, let us know within 30 days of purchase and we'll send you a different size or take it back and issue a full refund.

Customer Reviews

4.8 Based on 40 Reviews
5 ★
4 ★
3 ★
2 ★
1 ★
Write a Review Ask a Question
  • Reviews
  • Questions

Thank you for submitting a review!

Your input is very much appreciated. Share it with your friends so they can enjoy it too!

Filter Reviews:
Joseph H.
United States

Great workout/everyday underwear

I've owned a number of premium underwear brands, including Y's own SilverAir Merino variety. The fit of these is pretty much the same, which is to say it's very good. Enough support for workouts and HIIT, but not too much so that it's still very comfortable to wear as a daily driver. In fact, they are one of the most comfy boxer briefs I've ever worn. Compared to the merino underwear, these are a lot lighter and airier. The merinos are great to wear as travel underwear, as well as for gym days. These new ones would be equally good for gym days, but I'd feel a lot better about running in them since they're so much lighter. I can't attest to the durability of these yet since they're brand new, but because they are so thin and light, I hope they hold up as well as some of my other premium activewear. We'll see! Otherwise, highly recommended.

Tim M.
United Kingdom United Kingdom

10/10 customer service

Me: I want to order a bunch of stuff including xyz socks you are sold out according to your website. When will you get them in? You: I just checked the storeroom and I have 6 pairs. Do you want them? Me: awesome. Thanks so much !!

John B.
United States United States


If you love going commando but need some support - these are the best - right next to naked. Perfect.

Christophe T.
United States United States

Got some more!

I love it so much I ordered a few more :)

Spencer B.
United States United States

Love them!

This is my third pair of the silverair boxers! They have been ideal for my adventures and keep me from chaffing and discomfort. I've used them twice training full-time at the Shaolin temple in China and they were my go-to when I went hiking on the Everest base-camp trail this march in Nepal. I would highly recommend these and the silverair socks. Amazing products!