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Stand Out From The Pack - Shop Simply Ze Best
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
3,610 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.

Notify Me When Available

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 products is crafted to meet global standards and follows true-to-size measurements. Please refer to our size guide. for more details.
  • 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 Customer Happiness Team 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

Smiley Face Icon

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)

Customer Feedback

4.9
Rated 4.9 out of 5 stars
Based on 3,610 reviews
Total 5 star reviews: 3.4k Total 4 star reviews: 172 Total 3 star reviews: 16 Total 2 star reviews: 8 Total 1 star reviews: 10
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3,610 reviews
  • Adam
    Verified Reviewer
    Rated 5 out of 5 stars
    2/18/25
    Chur snake social

    Comfy as cool design and awsome idea with the paper that explains each snake. Cheers knobby team

  • Scott S.
    Verified Buyer
    Rated 5 out of 5 stars
    2/17/25
    Bom chicka wow wow

    Epic Gruts,

  • Jake P.
    Verified Buyer
    Rated 5 out of 5 stars
    2/13/25
    Love them

    Great undies super comfortable and highly recommend

  • Drew E.
    Verified Buyer
    Rated 5 out of 5 stars
    2/11/25
    Dope

    Comfy as

  • Shane R.
    Verified Buyer
    Rated 5 out of 5 stars
    2/9/25
    Chick chick boom trunks....look great

    Super comfortable and great length

  • Deraulle C.
    Verified Buyer
    Rated 5 out of 5 stars
    2/4/25
    Love it!

    Such a great set! Absolutely love the design. Please do more like this!!!

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A Club with Benefits

Club Members Get These Perks:
Legendary Savings
Legendary Savings

Save up to $13 per pair and get 15% off storewide!

Free Shipping
Free Shipping

Free AU Shipping on every order.

Your Club, Your Rules
Your Club, Your Rules

Pause, cancel, change size, add styles or adjust the frequency they arrive at any time!

V.I.P Access
V.I.P Access

V.I.P access to new designs, product releases, and occasional matching goodies!

Frequently Asked