Skip to main content

${cart_popup.message}

Free domestic shipping over $99 Shop Now
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
3,400 Reviews

Summer Bummer Men's Trunk

${ product_price | money }

${ chosen_product_member_price | money }

${ product_chosen.compare_at_price | money } ${(100 - ((product_chosen.price/product_chosen.compare_at_price)*100)).toFixed(0)}% Off

${ chosen_product_member_price | money} Members

  • 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 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

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)

Get The Full Collection

Out of Stock
Men's Long Leg / Summer Bummer
4.9
Rated 4.9 out of 5 stars
1,111 Reviews

Summer Bummer

Men's Long Leg
$33

$25 Members

Out of Stock
Bamboo Crew Socks / Summer Bummer
4.9
Rated 4.9 out of 5 stars
386 Reviews

Summer Bummer

Bamboo Crew Socks
$23

$20 Members

Summer Bummer / Car Seat Towel
5.0
Rated 5.0 out of 5 stars
2 Reviews

Car Seat Towel

Summer Bummer
$69

$59 Members

Customer Feedback

4.9
Rated 4.9 out of 5 stars
Based on 3,400 reviews
Total 5 star reviews: 3.2k Total 4 star reviews: 172 Total 3 star reviews: 13 Total 2 star reviews: 7 Total 1 star reviews: 12
Slide 1 selected
3,400 reviews
  • Amanda P.
    Verified Buyer
    Rated 5 out of 5 stars
    12/2/24
    Too good.

    My husband loves these undies - the only downside is they are such good quality they last too long and I don't need to buy more for him.

  • Jamie F.
    Verified Buyer
    Rated 5 out of 5 stars
    11/17/24
    Bloody awesome trunks

    Hi. I purchased these for 2 reasons.

    1: I needed to change from Briefs to trunks to eliminate chafing (I have a 35km charity walk to complete) and

    2: They are made from recovered plastic bottles (I am a plastic recycler, I turn household plastic waste back into a Food Grade material and back into a bottle, one of the best in the world) so I want to encourage this.

    They feel and perform perfectly. I want more. Thanks.

  • Sally S.
    Verified Reviewer
    Rated 5 out of 5 stars
    11/17/24
    Wonderful designs

    We have only known about and bought Knobbies for about 16 months….so great to get a chance to buy the earlier designs at a reduced price. Great value, love the native patterns. Would like it if Knobby made for women in the short design but larger sizes.

  • Sally S.
    Verified Buyer
    Rated 5 out of 5 stars
    11/11/24
    Great for kids too

    I bought several pairs for my grandkids. They love them. Swimmers and as shorts…not just underwear.

  • Sally S.
    Rated 5 out of 5 stars
    11/11/24
    Great design

    Love the gnome pattern. Great wearing and comfortable to all I give them too.

  • Henry O.
    Verified Reviewer
    Rated 5 out of 5 stars
    11/10/24
    Best Underwear Ever

    OMG this is the best feeling underwear I have ever owned and the designs are bright enough to be seen from outer space 😍

Reviews LoadedReviews Added

Join the Undie Club and save on every order.

LAST MONTHS DESIGN
Last Month's Design Last Month's Design Last Month's Design

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