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SuperPlus Leakproof® No-Show Boybrief

$39.00 CAD

Buy 3+ Save 15%, Buy 5+ Save 20%

Absorbs 7-11 super tampons

Front-to-back liner

Bonded seams prevent leaks

Machine washable

Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

| Black
Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

| General

Ashley has 39” hips and wears KNIX S

Color: Black

Size:

True to Size

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*

Build Your 3-Pack

SuperPlus Leakproof® No-Show Boybrief

Color: Black

Size:

Size:

SuperPlus Leakproof® No-Show Boybrief

Color: Black

Size:

Size:

SuperPlus Leakproof® No-Show Boybrief

Color: Black

Size:

Size:

Free Shipping on orders $100+

Shipping

Shipping

Processing Timelines

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order.

Delivery Time

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges

Orders over $100* CAD = Free Shipping (2-6 business days)

Orders under $100* CAD = $12 CAD Shipping (1-3 business days)

Orders delivering to NWT, Nunavut and Yukon are subject to $20 delivery fee.

*After discounts, before shipping and taxes.

First Pair Risk Free for 30 Days

Leakproof Underwear, Risk Free

Returns & Exchanges

New to leakproof? Your first pair is risk free for 30 days. Wear them, wash them, and see how they work for your body. Not right for you? We'll refund the item price (original shipping excluded). Prefer a different size or style? We also offer free exchanges. Just email info@knix.com and we'll take care of you.

Purchased leakproof before? Within 30 days of delivery you can exchange for another size, style, or store credit. We're unable to provide refunds on underwear. If you ordered multiple pairs, please open, wash, and wear one pair only before initiating an exchange.

Still have questions? View our full policy here.

Rewards Members Earn 39 Points

Product Description

Coverage you can count on, lines you can’t see. The SuperPlus Leakproof No-Show Boybrief provides a slightly fuller fit that hugs your curves and stays in place all day. Crafted from our signature moisture-wicking and anti-odor fabric, these panties keep you feeling dry and fresh even on your most challenging days. The extended gusset provides 360-degree protection, making these the ideal eco-friendly alternative to bulky pads. Available in inclusive sizes XS to 4XL, they are the perfect blend of athletic function and sophisticated protection.

Comfort-First Fit

Mid-rise boybrief silhouette with full bum coverage for a smooth, comfortable fit.

Ultimate Leakproof Protection

Our longest, most absorbent liner ever—front-to-back coverage without the bulk.

Day & Night Comfort

Buttery-soft stretch fabric moves with you, while bonded seams keep leaks contained and create a smooth, seamless look under clothing.

Machine Washable

Wash just like your regular underwear—easy, everyday care.

Zoom

Ashley has 39” hips and wears KNIX S | Black
| Black
Ashley has 39” hips and wears KNIX S | Black
Ashley has 39” hips and wears KNIX S | Black
| General

How to Choose?

Essential

  • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

  • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

  • Daily freshness. For sweat, discharge, period spotting, or backup protection.
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

  • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

  • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
PATENTED LEAKPROOF TECHNOLOGY

Our longest, most absorbent liner—ever.

Our original Fresh Fix Technology® features a built-in absorbent liner that soaks up about 7–11 super tampons’ worth of liquid—so you stay fresh, comfortable, and in control.

Soft Top Layer

Gently wicks moisture away while keeping you feeling fresh and odor-free.

4.3
Rated 4.3 out of 5 stars
Based on 64 reviews
Total 5 star reviews: 43 Total 4 star reviews: 7 Total 3 star reviews: 6 Total 2 star reviews: 3 Total 1 star reviews: 5
78%would recommend this product
64 reviews
  • Rated 5 out of 5 stars
    2 days ago
    Super Leakproof

    I really put these to the test. If you have a heavy period, I suggest getting at least two of these. I will purchase more.

    Juliana D.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Great material/fit

    Love them! Have them in a couple colours.

    Shelly Z.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Love the best!

    Absolutely love these they have been a life saver.

    Patricia M.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    SuperPlus Leakproof

    Awesome product. Feels good not to have to wear pads anymore after 30 years.

    Dorene K.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    It works!

    I recently tried period underwear and was pleasantly surprised. The texture is really soft and comfortable—honestly felt just like regular underwear, which made a big difference throughout the day.

    Most importantly, they actually worked. I felt protected and didn’t have to constantly worry about leaks, which gave me a lot more confidence when I was out and about. Definitely a convenient and reliable option to have in the rotation.

    Thecla H.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Great undies!

    They work as described. No leakage issues. And significantly more flattering than similar options from competitors. I’m going to order more.

    Virginia Y.
    Verified Buyer
  • Rated 5 out of 5 stars
    2 weeks ago
    Love

    Works perfectly and fits great

    Stacia A.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Fabulous product!

    Great help in store to pick right product for me.

    Dana P.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Amazing!

    I’m completely new to using period underwear and I am so happy I purchased a couple of pairs. It is so incredibly comfortable. I’ll have to buy more! Love these!

    Teala C.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Love the underwear

    I love the way it feels when sleeping not having to change is amazing

    Droudgie B.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Great!

    Good coverage, comfortable - great’

    Michelle S.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Amazing

    Love these, a perfect overnight option with the full coverage from front to back, so no more nighttime leakage or having to use two pads to get the length needed.

    Make this coverage level in the Dream Shorts please!!

    Kate
    Verified Reviewer

Your underwear questions, answered.