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Home / Up to 40% off Boyshort Underwear / SuperPlus Leakproof® No-Show Boybrief
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SuperPlus Leakproof® No-Show Boybrief

$39.00 CAD

3 for $99
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Absorbs 7-11 super tampons

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Front-to-back liner

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Bonded seams prevent leaks

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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

Absorbency: Ultra
Drop
Drop
Drop
Drop
Drop

Color: Black

Size:

True to Size

•

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*
Get FREE Express Shipping on all orders $125+

Shipping

HOLIDAY SHIPPING

Give the gift of Knix! To receive your order by Dec 24th, please order by the following dates.

Toronto, Ottawa, Montreal, Winnipeg, Regina, Calgary, Edmonton, Vancouver
Standard & Expedited: Monday, December 22

Urban Centres (excluding the above)
Standard: Wednesday, December 17
Express: Sunday, December 21

Rest of Canada
Standard: Sun, December 14*
Express: Thu, December 18*
*YK, NWT, NT, NL, and remote areas across Canada.

For locations serviced solely by Canada Post, please allow at least 5 additional days due to rotating strikes. This applies to P.O Box and RR addresses.

To avoid any additional delays during the rotating strikes, we will use alternate carriers when possible.

Please note: Weather conditions and carrier issues may cause delays. Delivery dates are not guaranteed.

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.
Year End Sale Return Policy

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.

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.

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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

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
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

Soft Top Layer

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

Our Best-Selling Underwear

Shop All Arrow Right

Super Leakproof® Dream Short

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30% off Select Colors

Color: Dark Cherry Limited Edition

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SuperPlus Leakproof® No-Show High Rise

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Leakproof UltraThin No-Show Bikini

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Leakproof UltraThin No-Show High Rise

$22.40 CAD
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Light Leakproof No-Show Bikini

$20.00 CAD
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Super Leakproof® Dream Boxer

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Leakproof UltraThin No-Show French Cut

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4.2
Rated 4.2 out of 5 stars
Based on 17 reviews
Total 5 star reviews: 10 Total 4 star reviews: 3 Total 3 star reviews: 2 Total 2 star reviews: 2 Total 1 star reviews: 0
76%would recommend this product
Write a Review (Opens in a new window)
17 reviews
  • Rated 4 out of 5 stars
    3 minutes ago
    Review.

    Boy brief. Want to try the brief. With a little bit of leg.

    Alice N.
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    3 days ago
    High Front Liner is GREAT, Waistband Is Meh

    Been hoping for a front to back liner for a long time (specifically the front, that’s where all my leaks were happening), so that part is great. The waistband though isn’t as comfortable as their other period underwear… it digs in a bit and isn’t as comfortable. Hoping for a waistband update for future releases.

    Deanna M.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    4 days ago
    No-show boybrief

    They are very comfortable, but I think they come up to high on my waist.

    Heather A. H.
    Verified Buyer
    Was this helpful?
  • Rated 2 out of 5 stars
    1 week ago
    Catastrophic Failure

    I bought these believing they would be better for overnight than the super boy briefs and the super plus briefs. They worked fine while I was laying down the first night, but when I stood up I had a catastrophic failure and ended up with blood all down my leg and by the time I got downstairs to the bathroom it was dripping on the floor. They changed the cut at the bottom of the boy short so it’s more like the briefs so there is no forgiveness if they get shifted at all. I’m done trying to get overnight protection from this brand. I’ve tried and the money … oh the money, I could have bought 6 years worth or more of overnight pads and be farther ahead.

    Sally Z.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Great Fit

    These fit well and are super comfortable and protect against leaks. I am very happy.

    Jessica K.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    J’adore!!!

    jessica
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    J’adore!!!

    jessica
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    WOW!!

    Fit perfectly and feel great.

    Liza S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    5 Stars

    I wasn't really sure what to expect. The idea of needing this sort of product made me really anxious and uncomfortable. Thankfully, these are very secure and comfortable. It's *almost* like bathing suit material, but softer. They aren’t too tight and don't dig into my skin. Smells don't escape it while wearing them, but when you're dealing with stuff / cleaning up, the smells are prevalent before washing. I rolled them up and washed these right away on delicate, and it was fine. I would purchase these again.

    Lunar
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    SUPER PURCHASE!

    These Boybriefs are great, just the right amount of body coverage, along with the fact they are the top absorbancy.

    Liza S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    love my no-show boybrief

    i have tried a few different ones. i like them all boy brief the best.

    Judy A.
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    3 weeks ago
    Good product, not for me

    I really like the extra coverage of this boy brief, but it turns out that extra leakproof is too much for me. I do like the fit. If you need more leakproof then this product would probably be great for you.

    Dee M.
    Verified Buyer
    Was this helpful?

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