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Home / Boyshort Underwear / Leakproof UltraThin No-Show Boybrief

Leakproof UltraThin No-Show Boybrief

$34.00 CAD

Mix, Match & Save: 3+ for $25 each
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Absorbs about 2.5 super tampons

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Invisible under clothes

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Moderate protection without the bulk

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Machine washable

| Black with White Polka Dot
| Black with White Polka Dot
| Black with White Polka Dot
| Black with White Polka Dot

Absorbency: Moderate

Moderate
Drop
Drop
Drop
Drop
Drop
about 2-4 super tampons
Ultra
Drop
Drop
Drop
Drop
Drop
about 7-11 super tampons

Color: Black with White Polka Dot 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

Sale & Last Call

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

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.
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Comfort-First Fit

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

Worry-Free Protection

Our newest leakproof innovation provides more absorbency without the bulk. Patented 360 LeakSeal™ technology locks in leaks at every edge.

Moderate Absorbency

Absorbs 2.5 super tampons worth of liquid—perfect for moderate flow days, light bladder leaks, and sweat. The carbon cotton gusset top layer keeps you dry.

No-Show Style

Buttery-soft and smooth fabric gives a seamless look and feel. Disappears under clothes, even leggings.

Easy to Wash

Machine washable just like regular underwear.

Zoom

| Black with White Polka Dot
| Black with White Polka Dot
| Black with White Polka Dot
| Black with White Polka Dot

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.

Our patented 360 LeakSeal™ technology locks in leaks at every edge. The ultra-thin liner absorbs about 2.5 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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4.8
Rated 4.8 out of 5 stars
Based on 86 reviews
Total 5 star reviews: 76 Total 4 star reviews: 6 Total 3 star reviews: 4 Total 2 star reviews: 0 Total 1 star reviews: 0
95%would recommend this product
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86 reviews
  • Rated 5 out of 5 stars
    3 minutes ago
    boybrief

    This is the first time I had this particular style. I really liked the fit. They are a little high waisted but felt very comfortable.

    Alaina N.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 hours ago
    Boybrief

    They are amazing. Love the boy short, comfortable, easy and do not show under my jeans . Love the new colors too. Thanks.

    GERI T.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 hours ago
    Very comfortable panty!

    Knix panties are so comfortable. I have several different styles and love them all.

    Susan U.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    Yesterday
    Comfortable and a great color

    This is my first time trying the boy shorts instead of bikinis and I really like them. No wedgies!

    Christina O.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    Love this style!

    Absolutely loving this style. The ultrathin is incredible - totally undetectable under clothes - even leggings! I’m on the shorter side at 5’1”, so these go up to my belly button, but I don’t mind.

    Hannah C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    Great coverage without being a high rise

    I really like the new style of the boybrief. It has great cheek coverage without being a high rise. Perfect compromise for those of us who want cheek coverage without the high waist peaking out at the top of your pants when you bend over. Also, I really like how Knix has made the gusset longer in comparison to the high rise as well better reinforced the seam of the gusset to the brief. I hope they do the same for all of their leak proof undies. The boybrief is my new favorite. I hope they make it in the super absorbency as well.

    Katherine G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 days ago
    Very comfortable

    Loved these underwear and found them to be very uncomfortable. Good quality!

    Teresa G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    6 days ago
    Great underwear comfy and cover everything well

    Great underwear comfy and cover everything well

    Kalambay E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    So Comfy

    I am loving this boy short style. I am wider across the butt and these provide the perfect cover. Shipping always fast!

    Sheryl C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    leakproof ultra thin no-show boy brief

    They fit me much better than the other styles I have tried!

    Valerie H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Love this style!!

    My all time favorite!! No show, easy fitting and great protection. The fit is like a second skin. No show under everything I wear!

    Jamie L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Very Comfortable

    First pair of boy shorts, comfortable, attractive, soaks up the leak. What more would you want?

    Laurie G.
    Verified Buyer
    Was this helpful?