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Men's Trunk / Monster Mash Men's Trunk / Monster Mash Men's Trunk / Monster Mash Men's Trunk / Monster Mash Men's Trunk / Monster Mash Men's Trunk / Monster Mash
4.9
Rated 4.9 out of 5 stars
3,605 Reviews

Monster Mash Men's Trunk

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  • Star IconUltra soft pin-hole BottleBlend® fabric
  • Star Icon Made from up to five plastic bottles
  • Star Icon Sanitized® bacteria and odour control

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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

This eerie design was concocted by our creepy creative, Phil Ramskill and inspired by vintage Halloween masks. Each style features a mash of all your favourite monster classics and a special glow-in-the-dark waistband that is guaranteed to give you the chills!
  • Ultra soft pin-hole BottleBlend® fabric
  • Made from up to five plastic bottles
  • Sanitized® bacteria and odour control
  • 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 / Monster Mash
Monster Mash Men's Trunk | ${ chosen_size_abbreviated } ${ chosen_product_price | money }
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Unique
Designs

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Unbeatable
Comfort

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Sustainably
Made

The Design Details
"Monster Mash" by Knobby (Artist Inhouse / Phillip Ramskill)

Customer Feedback

4.9
Rated 4.9 out of 5 stars
Based on 3,605 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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3,605 reviews
  • 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!!!

  • Michael S.
    Verified Buyer
    Rated 5 out of 5 stars
    1/23/25
    Cluckin Orsm

    As usual comfy as **** and amazing. Wants to have me crowing from the barn yard roof

  • kym r.
    Verified Buyer
    Rated 5 out of 5 stars
    1/22/25
    A classic!

    Finally added this classic design to my Knobby collection. As always, incredibly comfortable and well made. I really love this older design to, more so now that they're on 😆🍋🍋

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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!

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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!

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