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Men's Trunk / Summer Bummer Men's Trunk / Summer Bummer Men's Trunk / Summer Bummer Men's Trunk / Summer Bummer Men's Trunk / Summer Bummer Men's Trunk / Summer Bummer
4.9
Rated 4.9 out of 5 stars
3,514 Reviews

Summer Bummer Men's Trunk

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  • Star IconThe perfect all-rounder!
  • Star Icon Super soft BottleBlend™ eliminates chafe
  • Star Icon The first pair you'll grab after washing day

Choose Size: ${ chosen_size_abbreviated }

CONGRATULATIONS! SAVE 15%

Knobby Undie Club members save 15% on most products. Discount will automatically be applied once the item is added to your bag. To add another subscription, head over to your member portal.

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Same day dispatch if you order before 1pm AEST

In the sun-soaked waves, Groms rule, and the Sharks stand guard. With epic swells cranking, they fend off aggro surfers, so the young ones can hang loose.
  • Ultra soft pin-hole BottleBlend® fabric
  • Made from up to five plastic bottles
  • 4cm band with plush inner microfleece
  • Lightweight 160 gsm for versatility and comfort
  • 88% Recycled Poly
  • 12% Spandex
  • Tagless with printed care label
  • Made ethically and sustainably in China
  • THE STYLE: This best-selling style is the perfect all-rounder!
    Created from BottleBlend™, our very own recycled material, containing up to five plastic bottles. Flatlock seams for comfort and an inseam length of 15cm to reduce ride-up and eliminate cheeky chafe.
  • THE FIT: Each of our undies are made to a global standard. They are true-to-size, so order whatever size you would typically order for shorts. See our size guide.
  • THE MODEL: ${ chosen_product_model_description }

Each pair of Knobbys will arrive in a custom designed, certified kraft paper package or a sealed paper pouch and postage bag made with cornstarch, which is 100% compostable!

All our Australian printed papers and cardboards are recyclable, FSC certified and made carbon neutral, because we give a shit.

Our mission is to be the most sustainable underwear brand in the world.

FREE Standard Domestic Shipping for orders over $100

$9.50 Standard Domestic Shipping for orders under $100

Order before 1pm AEST on weekdays and we'll dispatch the same day!

Returns

Get in touch with our Support Ninjas within 30 days of receiving your Knobbys if you'd like to organise an exchange, refund, coupon or credit! More details

Men's Trunk / Summer Bummer
Summer Bummer Men's Trunk | ${ chosen_size_abbreviated } ${ chosen_product_price | money }
Lightbulb Icon

Unique
Designs

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Unbeatable
Comfort

Earth Heart Icon

Sustainably
Made

Step into a world of amazing underneaths that are ridiculously good and sustainably comfy

Main Product Image
Star Icon Exclusive Unique Design

In the sun-soaked waves, Groms rule, and the Sharks stand guard. With epic swells cranking, they fend off aggro surfers, so the young ones can hang loose.

Feature Image With Arrows
Star Icon Comfort & Fit

Experience unmatched comfort with our products:

  • Star IconThe perfect all-rounder!
  • Star Icon Super soft BottleBlend™ eliminates chafe
  • Star Icon The first pair you'll grab after washing day

We've designed it specifically for a snug fit that's perfect for everyday wear.

Made with Recycled Ocean Bound Plastic Bottles
Star Icon Sustainability

In a world striving for sustainability, our products stand out. Made from an innovative eco-friendly bottle blend fabric, they not only offer comfort but also reflect a commitment to a greener planet.

The Design Details
"Summer Bummer" by Knobby (Artist Inhouse / Phillip Ramskill)

Get The Full Collection

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Customer Feedback

4.9
Rated 4.9 out of 5 stars
Based on 3,514 reviews
Total 5 star reviews: 3.3k Total 4 star reviews: 172 Total 3 star reviews: 15 Total 2 star reviews: 8 Total 1 star reviews: 10
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3,514 reviews
  • Brittany W.
    Verified Buyer
    Rated 5 out of 5 stars
    1/6/25
    Topping the Christmas wish list!

    Got the sunshine ranch gift pack for me and my partner. Incredible design! We love it immensely. Always the first pick from the undie draw.

  • Sall S.
    Verified Buyer
    Rated 5 out of 5 stars
    1/5/25
    Magic

    Grandson’s favourite pair. Stretch well ,so great for the pool . Soft and well made.. He loves the fact they light up. All his favourite ones are the luminous designs.

  • Stephen S.
    Verified Buyer
    Rated 5 out of 5 stars
    1/2/25
    Best trunks on the market

    Mate, these Knobby trunks are the All Blacks of undies – absolute legends on the field (or, in this case, your backside). I grabbed these as a Christmas pressie, and let me tell ya, they’re the gift that keeps on giving.

    First off, the fit is so good it’s like they were custom-made by a bloke who knows the exact dimensions of your bum. They hug you in all the right places without riding up like a rogue sheep on the run. Honestly, it’s like wearing a cloud, if clouds were stylish, breathable, and didn’t make you look like a muppet.

    Durability? These bad boys could survive a full-on haka. Whether you’re smashing a workout, chasing the kids, or just lounging around watching the cricket, they stay comfy and keep their shape. No saggy bum here, bro.

    I’m already planning to stock up on more – because let’s be honest, once you’ve gone Knobby, there’s no going back. They’re the Richie McCaw of undies: reliable, top-notch, and always performing at their peak.

    10/10, I would recommend. If you’re still wearing those sad, stretched-out undies from 2015, do yourself a favour and upgrade. Your bum deserves better. Kia kaha, Knobby! 🩲

  • Stu G.
    Verified Buyer
    Rated 5 out of 5 stars
    12/30/24
    Awesome Xmas trunks!

    Great colours and fun images - love the Xmas scrapping haha. They’re super comfortable and my favourite pair of Knobby so far!

  • Harley W.
    Verified Buyer
    Rated 5 out of 5 stars
    12/29/24
    Love them.

    I like the colours. They are comfy. I had my doubts buying from. You guys thought it was going to be cheap and nasty. I'm glad I was wrong.

    Looking forward to buying more products from you guys.

  • Cory M.
    Verified Buyer
    Rated 5 out of 5 stars
    12/26/24
    Best men’s boxes in the world

    Absolutely love knobby will not buy anything else now awesome designs and well designed super comfortable would recommend to anyone

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