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Leakproof Cotton Boybrief

Boyshort period underwear in a soft cotton blend.
$35.00 CAD

Mix & Match: 3+ for $25 each
| Mushroom
| Mushroom
| Mushroom
| Mushroom
| General
| Mushroom
| General

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

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
    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

Drop
Drop
Drop
Drop
Drop
  • light period days
  • sweat
  • 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 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

Drop
Drop
Drop
Drop
Drop
  • extra heavy period days
  • overnight protection
  • light bladder leaks
  • 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
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.

4.2
Rated 4.2 out of 5 stars
Based on 194 reviews
Total 5 star reviews: 125 Total 4 star reviews: 26 Total 3 star reviews: 20 Total 2 star reviews: 8 Total 1 star reviews: 15
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
194 reviews
  • Rated 5 out of 5 stars
    3 minutes ago
    fav

    stays up is really comfortable soft and it is very absorbent. It’s perfect.

    Lisa M.
    Verified Buyer
  • Rated 5 out of 5 stars
    6 days ago
    Omg! I love these!

    They are so soft and stretchy, supremely comfortable with great coverage all the way up the back. Perfect for overnight.

    Jocelyn B.
    Verified Buyer
  • Rated 5 out of 5 stars
    6 days ago
    So comfy

    Knox items are comfortable and helps keep you confident.

    D P.
    Verified Buyer
  • Rated 4 out of 5 stars
    1 week ago
    Amazing

    Love these! They are comfortable and do the job.

    Katherine S.
    Verified Buyer
  • Rated 3 out of 5 stars
    2 weeks ago
    Not as much coverage as the old school boxers from knix, but it’s all right

    I like it when they’re underwear was thicker and more absorbent because I sweat. But they’re still cute and comfy.

    Rhonda H.
    Verified Buyer
  • Rated 5 out of 5 stars
    2 weeks ago
    Honestly life changing

    These are honestly life changing. I wear them to absorb sweat during my workouts in addition to wearing them during my cycle. I’m very happy I found these.

    Marci S.
    Verified Buyer
  • Rated 3 out of 5 stars
    2 weeks ago
    3 Stars

    Fabric is very soft and comfortable. However, the waistband tends to roll and bunchup on me:(

    Not sure if this due to my protruding belly; perhaps a hipster version of this will alleviate the rolling and bunching.

    Lavina
  • Rated 5 out of 5 stars
    3 weeks ago
    Awesome underwear

    I love wearing these during my period and when I workout. They are very absorbent and wash and wear well. My husband even likes the way they look.

    Marci S.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Comfy & Supportive

    These are 10/10! Gentle around all the edges and thin enough to wear with pants, even leggings

    Jackie
  • Rated 5 out of 5 stars
    3 weeks ago
    Leakproof cotton brief

    Love these

    Tracy C.
    Verified Buyer
  • Rated 4 out of 5 stars
    1 month ago
    Comfy

    Comfy and was way better than wearing a pad to bed.

    Katherine H.
    Verified Buyer
  • Rated 3 out of 5 stars
    1 month ago
    Nice cotton, weird gusset

    I love the cotton, but the gusset isn't fully connected to the actual underwear, so it's kind of strange.

    Chelsea M.
    Verified Buyer