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Boys Trunk / Plunder Down Under Boys Trunk / Plunder Down Under Boys Trunk / Plunder Down Under Boys Trunk / Plunder Down Under Boys Trunk / Plunder Down Under Boys Trunk / Plunder Down Under
5.0
Rated 5.0 out of 5 stars
244 Reviews

Plunder Down Under Boys Trunk

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  • Star IconSuper soft, not itchy, perfect for fussy kids.
  • Star Icon Made for school, sport or snuggles.
  • Star Icon Their new favourites!

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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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Notify Me When Available

Same day dispatch if you order before 1pm AEST

Batten down the hatches! A rowdy crew of sea rogues, led by a salty kraken, drifts through the waves, pilfering and plundering treasure from unsuspecting pirate ships. Once down under, the spoils are divvied up, because the best loot is shared loot!
  • Ultra soft pin-hole BottleBlend® fabric
  • Made from up to five plastic bottles
  • 3cm 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: Created from BottleBlend®, our very own recycled material, containing up to five plastic bottles. Ultra light and stupendously soft! This best-selling style is the perfect all-rounder, which breathe to keep you cooler than a tub of neapolitan ice cream.
  • 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

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Customer Feedback

5.0
Rated 5.0 out of 5 stars
Based on 244 reviews
Total 5 star reviews: 235 Total 4 star reviews: 9 Total 3 star reviews: 0 Total 2 star reviews: 0 Total 1 star reviews: 0
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244 reviews
  • Sally S.
    Rated 5 out of 5 stars
    11/13/24
    Nephew loves swimming in ocean

    Perfect for a sea fairing lad. Loves the Kraken. Best trunks ever he says.

  • Laikin V.
    Verified Buyer
    Rated 5 out of 5 stars
    10/14/24
    Glow cool!

    These are super different; but the glow just gives a little bit of fun !

  • Laikin V.
    Verified Buyer
    Rated 5 out of 5 stars
    10/14/24
    Aussie Aussie Aussie!

    This pair is so fun, not just for the olympics but the rugby that came to Australia too! Repping that green and gold is so much fun.

  • Laikin V.
    Verified Buyer
    Rated 5 out of 5 stars
    10/14/24
    Cool colours!

    My son loves the ocean and sea life so these kraken ones were super cool and fun!

  • Scott V.
    Verified Buyer
    Rated 5 out of 5 stars
    10/10/24
    Only have a few.

    I can't rate these high enough, I have worn Knobby underwear for years .

    but now my 4 year old son asks every week when is his new knobbys coming.

    The Hex appeal are his favourite to date, loves the glow in the dark.

  • Laikin V.
    Verified Buyer
    Rated 5 out of 5 stars
    9/19/24
    Love the beach!

    Perfect fit. Love the print. Always love getting a surprise each week!

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