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| Black
Light Leakproof No-Show Bikini
$25.00 CAD

Color: Black
Best Seller

Color: Black

Size:

Size:

Size and Fit Guide

Mix & Match: 3+ for $20 each
Rewards Members Earn 0 Points

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Home / All Underwear / Leakproof Cotton Boybrief
Best Seller

Leakproof Cotton Boybrief

$35.00 CAD

Mix & Match: 3+ for $25 each
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Absorbs about 3 super tampons

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Cotton comfort

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More absorbency without bulk

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Machine washable

| Mushroom
| Mushroom
| Mushroom
| Mushroom
| General
| Mushroom
| General

Absorbency: Moderate
Drop
Drop
Drop
Drop
Drop

Color: Mushroom Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*
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.
Easy Exchanges within 30 Days

Returns

Returns
Free Returns

Knix covers the return shipping fees for exchanges and refunds initiated through our Return & Exchange Portal. Exchange orders initiated through our Return & Exchange portal are also eligible for free shipping within the USA and Canada. Please note, the shipping fees on your original order are non-refundable.

Return Policy

Return policy varies by product, please check if your item is refund or exchange eligible by viewing our full policy here.

Sale & Last Call

Items discounted below 30% are eligible for size exchange or store credit. Items discounted 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.
Rewards Members Earn 35 Points

You May Also Like

Super Leakproof® Dream Short

$48.00 CAD

Leakproof Cotton Bikini

$25.00 CAD

Good to Go Seamless Bra

$48.00 CAD

Comfort-First Fit

A mid-rise boyshort with full coverage in the bum area.

Worry-Free Protection

An innovative floating gusset provides leak protection from every angle.

Moderate Absorbency

Absorbs about 3 super tampons worth of liquid—great for moderate flow days, light bladder leaks, and sweat.

Cozy Cotton-Blend

Soft cotton spandex feels luxurious against your skin.

Easy to Wash

Machine washable just like regular underwear.

Zoom

| Mushroom
| Mushroom
| Mushroom
| Mushroom
| General
| Mushroom
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Everyday Wear
  • • No leakproof protection
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    6-11 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 3-6 super tampons
  • cup
    about 1-2 menstrual cups

Light

Drop
Drop
Drop
Drop
Drop
  • • light period days
  • • sweat
  • • sweat and discharge
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

Drop
Drop
Drop
Drop
Drop
  • • moderate period days
  • • light bladder leaks
  • • sweat
  • tsp
    about 3-6 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-3 super tampons
  • cup
    about 0.5-1 menstrual cups

Ultra

Drop
Drop
Drop
Drop
Drop
  • • extra heavy period days
  • • overnight protection
  • • light bladder leaks
  • tsp
    13-17 tsp
  • pad
    3.5-4.5 regular pads
  • tampon
    7-9 super tampons
  • cup
    2-3 menstrual cups
FRESH FIX TECHNOLOGY®

Built-in protection that feels like nothing at all.

Absorbs about 2-3 super tampons worth of liquid.

Soft Top Layer

Soft Top Layer

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

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4.2
Rated 4.2 out of 5 stars
Based on 171 reviews
Total 5 star reviews: 110 Total 4 star reviews: 23 Total 3 star reviews: 16 Total 2 star reviews: 8 Total 1 star reviews: 14
78%would recommend these products
ComfortRated 4.3 on a scale of 1 to 5
EffectivenessRated 4.3 on a scale of 1 to 5
FitRated 0.1 on a scale of minus 2 to 2
Ease of UseRated 4.5 on a scale of 1 to 5
Write a Review (Opens in a new window)
171 reviews
  • Rated 2 out of 5 stars
    2 weeks ago
    the crotch isn't stitched in

    I like the boxer boybrief esp to wear when I work out at gym which is why I bought few pair of these but what I didn't realize is that the padded crotch isn't sewn in all the way around - uggg so it can get stuck and bunched up where you don't want! the stitch is only at back and front. disappointing considering I spent in total $200 on underwear from here.

    Angela B.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    3 weeks ago
    leakproof cotton

    fairly good, comfortable

    Dianne P.
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    3 weeks ago
    3 Stars

    Con’s: the padding it not secured down. It moves.

    Stacey
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    3 weeks ago
    4 Stars

    Havent worn yet but they do fit

    Coralee
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    4 weeks ago
    My favorite style and fabric but wish the seams in the back were not visible

    I have tried several different styles of knix and this one my favorite style and fabric, they are so comfortable, but I wish the seams in the back were not so visible:(

    KG
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Fit is amazing, as for leak proof, it's Knix, so it's amazing

    Juli
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    1 month ago
    Cotton brief

    Why not attach the leak proof part of brief to the brief? Makes brief very uncomfortable!?

    Candy S.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    Comfort

    Comfortable and effective .

    Valerie W.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    Comfort

    Comfortable and effective . Runs small. I’ve ordered from Knox on many occasions . I was disappointed that it was more of a cotton blend rather than just cotton. 😞

    Valerie W.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    Comfort

    Comfortable. Effective .

    Valerie W.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    Comfort

    Very comfortable. I like the variety of color

    Valerie W.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    Comfort

    Very comfortable . Provides sufficient leakproof .

    I was expecting a higher % cotton.,I prefer full cotton, so I was disappointed when it was more of a blended fabric so being called cotton was somewhat misleading.

    Valerie W.
    Verified Buyer
    Was this helpful?