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Pinatubo Seamless Sports Boxer

Pinatubo Seamless Sports Boxer

4.9
Rated 4.9 out of 5 stars
110 Reviews
Regular price $52.00 CAD
Regular price $52.00 CAD Sale price $52.00 CAD
Sale Sold out

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

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📦 $5 Flat Rate Shipping in US on all orders under $150

🚚 Orders ship within 1-2 business days

💸📦 Free Shipping in US over $150+

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.

5.0
Rated 5.0 out of 5 stars
Based on 75 reviews
Total 5 star reviews: 73 Total 4 star reviews: 2 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
100%would recommend this product
Slide 1 selected
75 reviews
  • 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

  • KENNETH E.
    Verified Buyer
    Rated 5 out of 5 stars
    Best I have found

    Just in the last year, I have purchase at least 8 different brands, all claiming their greatness! Problem is, none were great. Most were poor! One of my biggest irritants is a waist band that rolls. I absolutely hate it! Krakatoa is the first brand who's waistband actually stays flat. That alone gives them 5 stars, but the comfort is great also!

  • Joshua P.
    Verified Buyer
    Rated 5 out of 5 stars
    Comfortable.

    Nice wide waist band, quick drying and generally forgettable. And mean forgettable in the best way b/c I don’t think about them. If something stands out or catches yer attention there’s a reason. But thankfully this is one less thing I have to think about. I tried Shinesty, and Exofficio and Saxx. No bueno.

  • Richard S.
    Verified Buyer
    Rated 5 out of 5 stars
    The boxer briefs you've been looking for.

    I had medium expectations for the boxer briefs but they're better than I could imagine. My body temp. run warm naturally and these are so thin you barely even know you're wearing them - in a good way. Same with the support they provide. They are a little pricey but I believe you get what you pay for, so I'm buying more. Give them a try! If you don't like them, send them to me.

  • Shane T.
    Verified Buyer
    Rated 5 out of 5 stars
    Best undies I've ever worn

    Well, I never thought I'd be leaving a review on a pair of underwear, but here we are...

    These deserve it. I've tried MANY pairs of undies over the years, and these are by far the most comfortable I've ever worn. I had previously purchased one brand that I thought would be my "last" but the "pouch" design proved more trouble than it's worth, and involved an uncomfortable seam placed right behind my goodies. I'm also a pretty big guy (though shrinking by the day thanks to modern medicine along with diet and exercise changes) so that makes finding the right pair even more difficult. I also tend to be in the "grow-er" rather than "show-er" category, and the Pinatubo design is perfect for that.

    I'm not sure what magic they use in their fabric, but it is SO comfy...and the pouch is...how do I put this...absolutely PERFECT for my dangly bits. It's like the guys who designed these know even more about me and what's comfortable than I do. They also don't ride up, and the waistband doesn't roll down on me.

    I ordered one pair initially and fell in love, so I ordered half a dozen more pairs! I'm also planning to try a few more of their styles just for fun when I'm in the mood for something different.

    Finally, their customer service is AMAZING. I mentioned earlier that I'm losing weight. My first pair was an XXL, and (out of habit) I ordered the same size...but then realized my waist had dropped significantly in size since that order! They quickly updated my order to XL before…

  • Kathryn Y.
    Verified Buyer
    Rated 5 out of 5 stars
    Best Underwear Ever

    Krakatoa are hands down my husbands favorite brand and boxer. I’ve heard him complain for years about the waist rolling down on the million pairs of different styles and brands of underwear over the years and these are his favorite. He wears them to everyday and to the gym and says they never roll down and don’t bunch up around his legs. If you are finally ready to treat yourself (or your spouse) these underwear the best.

  • Peter S.
    Verified Buyer
    Rated 5 out of 5 stars
    You never knew how comfortable you could be

    For years I just wore whatever. Then I started trying many different brands and learned that it could be better.

    Then I tried Krakatoa, with their high end fabric and oh so gentle support of the boys and realized - wow. “No adjustment needed” was only step 1. Feeling like you are going commando all day but supported and cool, now that’s Krakatoa. I have since bought 18 pair and a day isn’t best without them.

  • George C.
    Verified Buyer
    Rated 5 out of 5 stars
    Size change

    I recently purchased Krakatoa underwear and had an outstanding experience, both with the product and the customer service. The quality of the underwear is top notch, and attention to detail that other companies just don’t have. My initial impression was “where have these underwear been my whole life?” Which faded pretty quickly when they started to ride up and cause just the slightest wedgie, not bad just enough to annoy the shit out of you. I had already made a full second order after how much I liked them at first. So I took a shot in the dark, and sent an email asking if they’d change the sizes on my whole order. Alex did that, and then some!

    Thats real reason I’m writing this, is the exceptional customer service I received. I had sent an email over asking if they’d change the sizes on my order (last minute). Alex responded promptly, ensured the correct size was updated, and my order was on the way. He even took the time to check in and ask if I was happy with the new size!

    I can’t recommend Krakatoa underwear enough! Not just for its superior quality, but also for the outstanding customer care. If anyone had told me the owner/ ceo of a company would email me to make sure I was satisfied with my order i would have thought they were crazy, but here we are.

    Couldn’t recommend Krakatoa enough! I’m already planning my next order. As long as Krakatoa is in the underwear game, they’ll have my business.

  • JOHN B.
    Verified Buyer
    Rated 5 out of 5 stars
    Best boxer briefs I’ve found.

    I bought a pair of these to try out. Quite honestly the first pair I bought quickly got a hole in them near the wasteband. However Krakatoa was very fast to replace them with a new pair. That pair held up great. Besides that I find them very comfortable, and I love the pouch. I’m a grower not a shower but have big balls and yet I love how the pouch is not only comfortable and supportive but how it accentuates my junk. I just bought four more pair of these because I love them so much. They are true to size and have at least a few color choices. I did also buy a pair of Vesuvius but because I’m a grower they fit a little less forming.

  • Scott M.
    Verified Buyer
    Rated 5 out of 5 stars
    Very comfortable

    I was wearing Manscape briefs and they kept creeping up. These stay put extremely well. The different type of fly intrigued me, but I really like it.