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Pinatubo Seamless Sports Boxer

Pinatubo Seamless Sports Boxer

4.9
Rated 4.9 out of 5 stars
174 Reviews
Regular price $43.00 CAD
Regular price $51.00 CAD Sale price $43.00 CAD
Sale Sold out

5" Inseam, Seamless Hems, Horizontal Fly, 3" Deep Pouch, 95% MicroModal

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The Details

The Easy-Access Sport Boxer

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.

With 5" inseam and seamless leg openings,
they will stay put no matter what you put them through.

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.

Form-fitting ultra-premium Tencel MicroModal fabric holds you softly and leaves you feeling fresh and cool.

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

Seamless legs that don't roll up or bunch up.

Inseam: 5 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 hello@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 hello@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.

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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

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.
The low-stitching 3" pouch is ultra-smooth, without holes, panels or gimmicks.
It just works.
It separates you from your thighs, ensuring comfortable support through all of life’s adventures.

micromodal v. cotton macro photo comparison

THE FINEST TENCEL MICROMODAL FABRIC
Exceptional Softness and Breathability.

No synthetics here -and no PFAS.

Feel softness like never before with an ultra-premium, hand selected 95% Tencel™️ 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.

Colorful waistbands in a square image.

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.

Close up of seamless hems

FLAT SEAMLESS HEMS For Legs That Stay Put.

Seamless hems are a game-changer, offering unmatched comfort and a sleek look under any outfit. Their innovative design ensures they stay put without pinching or leaving marks, providing a smooth, barely-there feel against your skin.

Perfect for any activity, seamless hems eliminate visible lines, giving you a flawless silhouette even under the most form-fitting pants. Enjoy the freedom of movement and the confidence of a perfectly polished appearance with the low-profile seamless hems on Pinatubo Seamless.

HEY ALEX, I HAVE QUESTIONS!

What should I know about the fit?

The Pinatubo Seamless Sports Boxer is designed with a 5" inseam.
The seamless legs are designed to stay put, but be long enough to cover an increased amount of your legs to add a layer of protection from friction.
The pouch is designed to be large enough to provide you room, while being double layered to also provide support and privacy for your privates.
The Horizontal Fly allows for super easy access.
All of this is benefited by our use of Tencel MicroModal fabric, which is incredibly lightweight and breathable.

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.

All Krakatoa Pouches are 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 SPORTS BOXER IS BEST FOR ME?

Each Sport Boxer comes with a specific pouch.
While they all share the same absurdly soft fabric, low profile seamless hems, and our unflippable waistband, their pouches are what set them apart.
Here is a quick guide:

  • Vesuvius boxer briefs with pouch shown with 5" inseam

    U-Shaped Caldera Pouch
    Low-Profile StealthFly
    Seamless Hems

    Learn More 
  • Haleakala boxer briefs side view with pouch shown in 5" inseam

    Closed, Lined StratoPouch
    4" Sealed Pouch
    Seamless Hems

    Learn More 
  • Pinatubo seamless side view with 5" inseam

    Top Horizontal Fly
    3" Low Seam Pouch
    Seamless Hems

    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.

4.9
Rated 4.9 out of 5 stars
Based on 215 reviews
Total 5 star reviews: 202 Total 4 star reviews: 6 Total 3 star reviews: 4 Total 2 star reviews: 2 Total 1 star reviews: 1
97%would recommend this product
Slide 1 selected
215 reviews
  • John
    Verified Reviewer
    Rated 5 out of 5 stars
    Backpacking and River Plunge Approved

    After wearing them a few times I decided to take them on a 3 day, 2 night backpacking trip. I did some cold plunging in the river with them and just let them air dry for a bit before throwing my pants back on over top of them.

    I was super impressed with how well they dried off and how comfortable they were for the extended timeframe of use. Will be buying several more pairs.

  • Trey S.
    Verified Reviewer
    Rated 5 out of 5 stars
    Great for guys who aren't packing much!!

    They feel comfortable and the legs don't seem to ride up very much. I'm very happy with the support it offers and it cradles everything. Even if you have a small penis these underwear make it look great unlike other pairs on here. 10/10

  • Paul N.
    Verified Buyer
    Rated 5 out of 5 stars
    Spreading the love

    I love these underwear!!!! I was visiting some friends for the weekend. There were three couples total. The guys started a conversation about men’s underwear and I mentioned Krakatoa but neither had ever heard of the brand. So while I was singing high praises and bragging about how comfortable my boys have been down there, I realized that when I packed for the weekend I threw two brand new still packaged pairs of Pinatubo boxer briefs into my bag. So I went and grabbed them and gave each guy a pair! That was definitely a party first for me!!! lol! I can’t wait to hear their feedback. Thanks again, Alex for giving the world such a superior product!!!

  • Cindra L. H.
    Verified Buyer
    Rated 5 out of 5 stars
    Extraordinary!

    I got these for my boyfriend - WOW! What a difference there is from "ordinary" briefs! They looked fabulous on him and gave him a completely different silhouette than the perfectly nice briefs he usually wears. It made his manly features much more well-defined. I have no idea how they will look under his trousers because we simply didn't get that far! However, we will try to take a picture soon because it was all the pictures that were provided that sold me on the product - as well as the fact that this is a small business, the title of the company and names of the various styles are genius, and the product is very well made. And btw, the fabric is amazing!.

  • Michael S.
    Verified Buyer
    Rated 5 out of 5 stars
    The Horizontal Fly Is Genius

    I’ll admit, this may sound a little silly. The first time I went to use the fly on my new pair of Krakatoa Pinatubo Boxer Briefs, I was caught off guard—it’s horizontal, not vertical. After 56 years of muscle memory, that small change felt surprisingly foreign. But after just a few days of wearing them, I’ve completely adjusted, and now I actually prefer it. The horizontal design makes access quicker and easier, eliminating the awkward fumbling that comes with a traditional vertical fly.

    Beyond that clever design, the briefs live up to every claim the brand makes. They don’t ride up throughout the day, the waistband stays perfectly flat without digging in, and the overall fit is impressively comfortable. The fabric feels supportive yet breathable, striking a balance that makes them ideal for both everyday wear and more active situations.

    In short, Krakatoa has taken something as ordinary as boxer briefs and elevated them with thoughtful design and genuine comfort. What started as a seemingly high-priced curiosity has quickly become my new favorite pair of underwear and worth every penny. My wife spends about the same amount on her underwear for a lot less material.

  • Greg C.
    Verified Buyer
    Rated 5 out of 5 stars
    BUY. THEM. NOW!

    I have worn Duluth Dang Soft's forever. Saw a post on these and thought I'd give them a shot. The moment I put them on ... SOLD! Immediately ordered 8 more pairs. Sooooo comfortable, feels like they're not even there. Well Done! Sorry Duluth ....

  • marc v.
    Verified Buyer
    Rated 5 out of 5 stars
    Great Product

    Krakatoa is an excellent example of a company that understands its customer and their energy goes into making the customer one that repeatedly returns to acquire more products. Keep doing a great job. Many Thanks.

  • Hubert H.
    Verified Buyer
    Rated 5 out of 5 stars
    Krakatoa has done impossible

    After all these years…Perfection! I have searched everywhere and gambled buying random brands and always been disappointed again… and again. Those days are over! Comfort.. it’s like wearing a second skin. Does it get moved or ride up? No it stays in place. Easy access? Yep it’s there and best of its kind. Looks… They just don’t have style it’s whole another class of its own and it knows it. Krakatoa thank you for this blessing. My time wasted looking is over and now I look forward on.

  • Ty H.
    Verified Buyer
    Rated 5 out of 5 stars
    Nicest underwear I've ever bought

    For the majority of my life I've bought underwear from my local mall or Walmart, but lately wanted to try something nicer. After reading a lot of good things on reddit I decided to try these and I'll definitely be buying some more. Softest material I've ever felt and I actually love the fly design on these. If the durability is equal to the fit and comfort I'll probably be sticking with the krakatoa brand from now on.

  • Bobby K.
    Verified Buyer
    Rated 5 out of 5 stars
    Real comfort

    I've tried a lot of underwear, was using 32 degrees Cool, but these are far beyond anything I have tried. Not more trying- these are my undies .