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Home / MNTD Men's Basics / Men's ActivTemp™ Trunk 3"

Men's ActivTemp™ Trunk 3"

$26.00 USD

Buy 3+ Save 15%, Buy 5+ Save 20%

Active temperature regulation

Moisture-wicking Pristine Pouch™

Super breathable with odor protection

Ultra-soft & stretchy moisture-wicking fabric

Won’t ride up, bunch, or sag

Men's ActivTemp™ Trunk 3" shown front-facing against a light gray background
Front view of model wearing the Men's ActivTemp™ Trunk 3" highlighting the coverage and fit
Back view of model wearing the Men's ActivTemp™ Trunk 3" highlighting the coverage and fit
Text on Image: Super breathable temperature regulating fabric that cools down as you heat up.
Text on Image: Double-layer Pristine Pouch™ wicks away moisture while providing odor protection.

Color: Ice Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Build Your 3-Pack

Men's ActivTemp™ Trunk 3" shown front-facing against a light gray background

Men's ActivTemp™ Trunk 3"

Color: Ice Limited Edition

Size:

Size:

Men's ActivTemp™ Trunk 3" shown front-facing against a light gray background

Men's ActivTemp™ Trunk 3"

Color: Ice Limited Edition

Size:

Size:

Men's ActivTemp™ Trunk 3" shown front-facing against a light gray background

Men's ActivTemp™ Trunk 3"

Color: Ice Limited Edition

Size:

Size:

Free Shipping on orders $100+

Shipping

Shipping

Processing Timelines

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order. Once an order is placed, we cannot guarantee any address updates, order changes or cancellations. Orders placed on Friday after 1PM will not be shipped until the following Monday.


Split Shipments

Most orders will ship from a single warehouse. However, we occasionally ship from a combination of warehouse locations, so you may receive your order in multiple parts. If items from your order ship in separate packages, we’ll send you tracking information for each package when it becomes available.

Delivery Timelines

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines do not include processing times. See above for details. All transit times are measured in business days which are Monday-Friday, excluding holidays.

Please note, all shipping timelines are estimates and are not guaranteed.

We are not able to ship to US territories (including Puerto Rico, U.S. Virgin Islands, Guam, Northern Mariana Islands and American Samoa) at this time.
Easy Exchanges within 30 Days

MNTD

Returns & Exchanges

Holiday Return Policy
Eligible items purchased online or in stores between November 2, 2026 and December 31, 2026 may be returned through January 29, 2027. All other purchases fall under our 30 day Returns Policy.

Standard Return Policy
Built for real life. Here's how returns and exchanges work for MNTD.

  • MNTD Tops — Eligible for return or exchange within 30 days of delivery. Wear it, wash it, and see how it works. Still not happy with the fit? Let us know and we'll sort it out.
  • MNTD Underwear — Eligible for exchange or store credit within 30 days of delivery. Wear them, wash them, see how they work. We're unable to provide refunds on underwear. If you ordered multiple pairs, please open, wash, and wear one pair only before initiating an exchange.
  • MNTD Socks & Sale — Final sale. No refunds, store credits, or exchanges.

Still have questions? View our full policy here.
Rewards Members Earn 26 Points

"Perfect boxers for a busy life that makes for an easy transition between biking around, hitting the gym, and grinding it out at work. Great temperature regulation and love the wind blocking of the pouch for cold weather sports."

- Connor | Verified Reviewer

Product Description

The perfect hybrid of athletic support and modern style. The MNTD Active Boxer Trunk is designed for the man who moves. With a sleek, shorter-leg silhouette, these trunks are the ideal base layer for workout shorts or slim-fit joggers. The breathable, four-way stretch fabric provides a "barely there" feel, while the stay-put waistband prevents rolling and bunching. From a morning HIIT session to your daily commute, experience breathable men’s trunks that look as good as they perform.

Keep Your Cool

Active temperature regulation that cools you down as you heat up.

Stay Spotless

The Pristine Pouch™ wicks away moisture and keeps it from showing through.

Fresher for Longer

Super breathable, anti-odor Mint Condition Technology™ for optimal freshness.

Love the Feel

Ultra-soft, moisture-wicking fabric that keeps you dry and fresh. Built to move comfortably with you, while the waistband stays in place without digging in.

No Adjustments Necessary

Designed to prevent sagging, bunching, or ride-up with durable construction that holds its shape over time.

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Underwear that overperforms

Active Cooling. Targeted Freshness.

Performance underwear with active temperature regulation and a moisture-wicking pouch designed to keep you cool, dry, and comfortable all day.

Active Temperature Regulation

Fabric responds to your body temperature, cooling you as you heat up.
4.2
Rated 4.2 out of 5 stars
Based on 22 reviews
77%would recommend this product
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22 reviews
  • Rated 3 out of 5 stars
    2 days ago
    New underwear

    I felt the underwear could be a little more substantial. I noticed the top portion that holds up the pants, curled.

    DT
    DAVID T.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 1 out of 5 stars
    1 week ago
    active trunk 3

    nothing like described ride up immediately not as good as regular bamboo underwear

    VC
    Vittorio C.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 2 out of 5 stars
    2 months ago
    NOPE!

    Let's start with the positive. A dribble did not show. Now the rest. After the dribble continued to feel wet. The absorbency area tapers smaller, so if you're a little to either side you're wet and bound to show a spot anyway.

    DB
    David B.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    Love theses

    Keeps you cool through out day

    BO
    Bradley O.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 4 out of 5 stars
    2 months ago
    Great Underwear

    Honestly I've tried so many different types, from Saxx, MyPackage, BNTH and other. I really do like these. My only complaint is I should've bought the 5" instead of the 3". The previous ones are about 4", so the 3" feels short for me.

    Otherwise, great underwear.

    SB
    Shaun B.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    2 months ago
    ActivTemp trunk

    Very nice, move with you, comfortable.

    GP
    George P.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 2 out of 5 stars
    2 months ago
    Ride up

    Material rides up

    Nobody likes a weggie

    JB
    John B.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 4 out of 5 stars
    2 months ago
    Inseam

    There is no way this inseam is 1" Needs an inch added!!

    WJ
    William J. M. J.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Love them!

    Highly comfortable & love them!

    GK
    Garrett K.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Fabulous purchase

    Purchased these for my husband. He absolutely loves them. He now has 5 pair. I will continue to purchase these

    K Profile picture for Knix
    Knix
    3 months ago

    Hey Christine!

    This is amazing! We're so thrilled your husband is loving his ActivTemp™ Trunks. Five pairs and counting - that's the best compliment we could get!

    Team Knix

    CD
    Christine d.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    3 months ago
    Love these undies

    Man! These fit well! And the waist band is not too tight not too slack. The pocket fit my jewels nicely. I ordered a 7-pack a week later!

    DC
    David C.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    great product

    great product

    RM
    robert m.
    Verified Buyer
    Reviewing
    Men's ActivTemp™ Trunk 3"
    Was this helpful?

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