Skip to product information
1 of 13

Pinatubo Trunks

Pinatubo Trunks

4.8
Rated 4.8 out of 5 stars
1,325 Reviews
Regular price $ 30.00 USD
Regular price $ 25.00 USD Sale price $ 30.00 USD
Sale Sold out

Horizontal Fly, 95% MicroModal, Stay Flat Waistband, 2" inseam

Machine wash on cold, Dry on medium

Size Guide
Size
Color

Save with Bundle Pricing

Save 10% when you buy 3+ pairs.
Save 20% when you buy 7+ pairs.

Mix and match items to unlock savings.
Savings automatically added to your cart.

📦 Orders ship within 1-2 business days

The Details

The Trunk That Got a Fly.

Pinatubo’s top-access horizontal fly offers a quick-draw, one-handed action, making it easy to reach in and go—putting the ‘fun’ back in functional.
The large, 3-inch deep front pouch, with minimal stitching, is designed to keep you separated from your thighs and comfortably supported all day long.

Wide and ultra-smooth waistband won't flip or mark your skin.

Legs that don't roll up or bunch up.

Inseam: 2 inches

52 Wash Guarantee. Because we can.

1st Order Fit Guarantee

Our number one goal is that you're happy with your purchase.

Try on a single pair and make sure it's perfect for you.

If you bought multiple pairs, make sure you try ONLY ONE PAIR for fitting purposes.

After this first pair, all underwear must be unworn, unwashed, in the original condition and packaging you received them in for a refund.

Due to the nature of our product we cannot accept returns of worn products. We will only be able to provide store credit for worn products limited to your first pair.

Please contact us directly at support@krakatoaunderwear.com to discuss options.

52 Wash Guarantee

We want you to feel confident making your purchase from us. We provide a 52 Wash Guarantee which is triggered by either 52 washes or 12 months from the date of purchase. If your item has any structural damage resulting from a manufacturer's defect before 52 washes or 12 months, we'll replace them for just the cost of shipping.

The guarantee excludes damage caused by neglect or abuse, by intentional damage, accidental damage, color fade, pilling, stains of any kind, and deliberate attempts to damage the product.

Applies to any product purchased, does not apply to any product provided as a replacement.

Send us an email at support@krakatoaunderwear.com with the subject "52 Wash Guarantee Claim". Please be sure to include photos of the damage. We will be in touch shortly after.

Full details can be found HERE.

Free US Shipping on Orders $75+

We provide free basic shipping for all orders over $75 in the United States.

View full details

Find your size

You'll need a a pair of your existing underwear, a flat surface, and a measuring tape.

I'm Alex, I made these for you.

THE FEATURES YOU ASKED FOR

Every little detail was obsessively fine-tuned, to deliver you an underwear experience like no other: 

FULL SUPPORT WITH A FLY
Putting the Fun in Functional

Say goodbye to readjustments!

Pinatubo’s 3” deep pouch design with minimal stitching keeps you comfortable and secure all day.
The one-handed, top-access horizontal fly provides effortless reach into the goods.
It separates you from your thighs, ensuring comfortable support through all of life’s adventures.

THE FINEST MICROMODAL FABRIC Exceptional Softness and Breathability.

No synthetics here -and no PFAS.

Feel softness like never before with an ultra-premium, hand selected 95% MicroModal fabric. We source only the best MicroModal because comfort is our #1 goal. (Learn about MicroModal). We just add 5% of Spandex to allow for it to move with you.

We never skimp on the quality of our fabrics and materials, neither on the craftsmanship. These products go on your softest, most sensitive parts. We won't settle for anything less than the very best.

SOFT STITCH HEMS For Legs That Stay Put.

Our Trunks are perfect for active guys who prefer a shorter leg that fits comfortably under pants or shorts. Whether it’s daily wear, hiking, sports, or lounging, they transition effortlessly from gym shorts to suits with aplomb.

UNFLIPPABLE WAISTBAND
Art On Your Body.

Our waistbands are wide, smooth, don't leave marks, and are truly unflippable, offering a secure fit that prioritizes style and your comfort over branding. We focus on modern designs rather than flashy logos, framing your body beautifully.

Inside, you’ll find positive, self-affirming words designed to motivate you daily, inspiring you to be a better person to yourself, and to those around you.

Experience the perfect blend of style and substance with a waistband that uplifts and empowers you.

HEY ALEX, I HAVE QUESTIONS!

What should I know about the fit?

The Pinatubo Trunk features a 2” inseam, with legs designed to stay put but may ride up slightly during active use.
The 3" deep pouch offers ample space with a top-acess horizontal fly for one-handed quick-draw action, while its double-layered construction provides both support and privacy.
All of this is enhanced by our use of our high-grade 95% MicroModal, an incredibly lightweight and breathable fabric.

What if I'm in between sizes?

Our sizes run pretty true and the materials do have stretch to them.

But if you're not sure which size is going to be the best for you, consider these three things:- Your waist in inches (pants size is OK).

- If your legs touch at the thighs.
- If you have a small, normal or large butt.

If your legs touch and your butt is large, you might jump a size.

If you have a small butt and thin legs, you can downsize.

What's MicroModal fabric?

In a word. Soft.

Really soft, our MicroModal is hand-selected to be of the highest grade available.

MicroModal is a modern technical fabric that is manufactured with cellulose from renewable Beechwood trees. Compared with Cotton, it's odor-resistant, 3 times softer, 50% more breathable, and it's not nearly as polluting or water-wasting.

Why such a big pouch?

Men come in all different shapes and sizes but for years underwear failed to respect our anatomy.

Our pouch is designed for the majority of men out there to accommodate and coddle. It's a blend of being soft with some stretch where needed, but also supportive for all day comfort. You won't need to adjust yourself anymore, because sticking to your legs is a thing of the past.

When will my item ship? How long will it take to arrive?

Please allow 2-4 days for processing, and the usual shipping times from the USPS or UPS: inside the US you can expect to see your package between 3-6 days.

We'll send you a confirmation email with your tracking information as soon as it ships.

If you have any questions or don't receive an email, feel free to reach out via our Contact Us Page.

What is your returns and refunds policy?

All returns are available for 60 days following their delivery date.

We’re happy to accept any items that are unused, unopened, unworn, and in their original packaging.

WE ARE UNABLE TO ACCEPT ANY PRODUCTS THAT HAVE BEEN WORN.

We strongly encourage you to add shipping insurance and hassle free returns to your orders as it appears in the cart, especially if it’s your first order.

We strongly recommend that you only try on only one pair for sizing purposes.

You can start a return at any time in our Returns Portal.

Given the nature of our product, and for health and safety reasons, we are unable to provide exchanges at this time.

Buyer will be responsible for any associated return shipping costs.

How do I wash my Krakatoa?

Krakatoa is quite resistant to shrinking and fading, but machine-washing them in cold water using the delicate setting and drying in low heat will keep them looking fresher for longer.

Please do not bleach, iron, or dry clean your boxer briefs or trunks. You can also wash it by hand and lay it flat to dry, for great results.

What's your 52 Wash Guarantee?

We want you to feel confident making your purchase from us. We provide a 52 Wash Guarantee which is triggered by either 52 washes or 12 months from the date of purchase. If your item has any structural damage resulting from a manufacturer's defect before 52 washes or 12 months, we'll replace them for just the cost of shipping.

The guarantee excludes damage caused by neglect or abuse, by intentional damage, accidental damage, color fade, pilling, stains of any kind, and deliberate attempts to damage the product.

Applies to any product purchased, does not apply to any product provided as a replacement.

Send us an email at support@krakatoaunderwear.com with the subject "52 Wash Guarantee Claim". Please be sure to include photos of the damage. We will be in touch shortly after.

Full details can be found HERE.

WHICH TRUNK IS BEST FOR ME?

Each Krakatoa Collection comes with a specific pouch and hem.
While they all share the same absurdly soft fabric and unflippable waistband, their pouches and hems are what set them apart.
Here is a quick guide:

  • 3" Low-Seam Pouch
    Top Horizontal Fly
    Stitched Hems
    2" Inseam

    Learn More 
  • The Original
    3" Sealed Pouch
    Stitched Hems
    2" Inseam

    Learn More 
  • U-Shaped Caldera Pouch
    Low-Profile StealthFly
    Seamless Hems
    1.5" Inseam

  • Sealed, Lined StratoPouch
    4" Sealed Pouch
    Seamless Hems
    1.5" Inseam

    Learn More 

CHECK OUR REVIEWS

See how we have impacted guys from all walks of life.
Our products are only as good as the impact they have on those that experienced them.

4.8
Rated 4.8 out of 5 stars
Based on 1,325 reviews
Total 5 star reviews: 1.2k Total 4 star reviews: 112 Total 3 star reviews: 24 Total 2 star reviews: 5 Total 1 star reviews: 6
91%would recommend these products
Slide 1 selected
1,325 reviews
  • Thai C.
    Verified Buyer
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    Exceed expectations

    Second purchase within 6 months! Flawless fit!!!

  • Travis S.
    Verified Buyer
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    Best underwear on market

    The search is over I will always wear these

  • Walter M.
    Verified Buyer
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    I’ve tried them all. These are by far the best.

    Believe me, I’ve tried them all. These ball hammock ones, the ones that separates your franks and beans, the ones that supposedly don’t ride up, the ones that guard against sweat… like… all of them. These, are by far and away superior to any of the ones I have tried. They fit well, ever ride up, don’t hold moisture, waist band does not fold, I have never felt a more comfortable pair of underwear ever. Stop playing around with all the other pretenders and get the real deal.

  • Richard A.
    Verified Buyer
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    My new favorite trunks

    I ordered a few styles to try them out and really love these. They are very well made, comfortable, and hold up well (so far - 2 washes in). I hate when the waistband rolls over, and these just don’t to that!

    Would definitely recommend!

  • Travis
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    5 Stars

    Great fit! Great pouch! Great fly!

  • James A.
    Verified Buyer
    INTRO PAIR TRUNK
    Reviewing
    INTRO PAIR TRUNK
    Rated 5 out of 5 stars
    Comfortable

    Extremely comfortable, like barely wearing anything. Most importantly the wife loves they way they look. Highly recommended!

  • Glenn
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    5 Stars

    ⭐️⭐️⭐️⭐️⭐️

  • Charles D.
    Verified Buyer
    INTRO PAIR TRUNK
    Reviewing
    INTRO PAIR TRUNK
    Rated 5 out of 5 stars
    Total Comfort

    Tried the intro pair of trunks and must say they are 100% comfortable! You do not even realize you have underwear on, without any adjusting or pulling etc. I’ll be buying more!

  • CHARLES B.
    Verified Buyer
    Pinatubo Trunks
    Reviewing
    Pinatubo Trunks
    Rated 5 out of 5 stars
    Nice...

    Very comfortable 😁

    Love the horizontal fly 😄

  • Dennis B.
    Verified Buyer
    INTRO PAIR TRUNK
    Reviewing
    INTRO PAIR TRUNK
    Rated 5 out of 5 stars
    Love them

    These are very comfortable. The waist band is very strong and comfy. Did not roll like all the others. I almost forgot I had them on they were so nice. I will be getting some more of them in the future.

Reviews LoadedReviews Added