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SuperPlus Leakproof® No-Show Boybrief

$39.00 CAD

Mix, Match & Save: 3+ for $33 each
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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

Color: Black

Size:

True to Size

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*

Build Your 3-Pack

Ashley has 39” hips and wears KNIX S | Black

SuperPlus Leakproof® No-Show Boybrief

Color: Black

Size:

Size:

Ashley has 39” hips and wears KNIX S | Black

SuperPlus Leakproof® No-Show Boybrief

Color: Black

Size:

Size:

Ashley has 39” hips and wears KNIX S | Black

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

Leakproof Underwear, Risk Free
Trying leakproof underwear for the first time? Your first pair is completely risk free for 30 days. Wear them, wash them, and see how they work for your body. If they’re not right for you, we’ll refund your first pair. Prefer a different size or style? We also offer free exchanges.

How it works:

  • Risk free applies to leakproof underwear on your first order
  • Refund covers the item price (original shipping excluded)
  • Just email info@knix.com and we’ll take care of you

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

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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

  • 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

Soft Top Layer

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

4.1
Rated 4.1 out of 5 stars
Based on 44 reviews
Total 5 star reviews: 27 Total 4 star reviews: 6 Total 3 star reviews: 4 Total 2 star reviews: 2 Total 1 star reviews: 5
75%would recommend this product
44 reviews
  • Rated 5 out of 5 stars
    3 minutes ago
    Love them

    They are extremely good

    PATRICIA D.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Love

    The high coverage!

    Allison L. F.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Amazing

    Just what I needed for those unfortunate bladder leaks

    Tooks
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    J’adore

    Très bien, confortable et efficace

    Keyla O.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Comfort and confidence

    Super comfortable! Confidence in zero leaks! As a nurse on her feet every day with sometimes no time to go to the bathroom regularly, I love the Knix superleak proof boy shorts. They don’t feel bulky and don’t show through the scrub pants like the store bought bladder control/ period products. I highly recommend them to all my friends.

    Serena B.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Great overnight

    Works well overnight got my teen daughter.

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

    Really great

    Miguel S.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Très confortable et fait très bien son travail

    Martyne
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Très confortable et fait sa job !

    Martyne
  • Rated 5 out of 5 stars
    1 month ago
    New to me

    Love these. They fit so well I ordered 4 more

    Gale S.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Super!

    Annie
  • Rated 5 out of 5 stars
    1 month ago
    Good underwear

    Great

    Pamela B.
    Verified Buyer