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SuperPlus Leakproof® No-Show Boybrief

$39.00 USD

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

Megan has 36.5” hips and wears KNIX S | Twilight Navy

Megan has 36.5” hips and wears KNIX S

| Twilight Navy
Megan has 36.5” hips and wears KNIX S | Twilight Navy

Megan has 36.5” hips and wears KNIX S

Megan has 36.5” hips and wears KNIX S | Twilight Navy

Megan has 36.5” hips and wears KNIX S

| General

Megan has 36.5” hips and wears KNIX S

Color: Twilight Navy Limited Edition

Size:

True to Size

Size:

Size and Fit Guide

Build Your 3-Pack

Megan has 36.5” hips and wears KNIX S | Twilight Navy

SuperPlus Leakproof® No-Show Boybrief

Color: Twilight Navy Limited Edition

Size:

Size:

Megan has 36.5” hips and wears KNIX S | Twilight Navy

SuperPlus Leakproof® No-Show Boybrief

Color: Twilight Navy Limited Edition

Size:

Size:

Megan has 36.5” hips and wears KNIX S | Twilight Navy

SuperPlus Leakproof® No-Show Boybrief

Color: Twilight Navy Limited Edition

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. Once an order is placed, we cannot guarantee any address updates, order changes or cancellations. Orders placed on Friday after 1PM will not be shipped until the following Monday.


Split Shipments

Most orders will ship from a single warehouse. However, we occasionally ship from a combination of warehouse locations, so you may receive your order in multiple parts. If items from your order ship in separate packages, we’ll send you tracking information for each package when it becomes available.

Delivery Timelines

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines do not include processing times. See above for details. All transit times are measured in business days which are Monday-Friday, excluding holidays.

Please note, all shipping timelines are estimates and are not guaranteed.

We are not able to ship to US territories (including Puerto Rico, U.S. Virgin Islands, Guam, Northern Mariana Islands and American Samoa) at this time.

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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Megan has 36.5” hips and wears KNIX S | Twilight Navy
| Twilight Navy
Megan has 36.5” hips and wears KNIX S | Twilight Navy
Megan has 36.5” hips and wears KNIX S | Twilight Navy
| 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.

4.0
Rated 4.0 out of 5 stars
Based on 44 reviews
Total 5 star reviews: 25 Total 4 star reviews: 7 Total 3 star reviews: 4 Total 2 star reviews: 2 Total 1 star reviews: 6
73%would recommend this product
44 reviews
  • Rated 5 out of 5 stars
    22 seconds 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
    2 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
    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
    Good underwear

    Great

    Pamela B.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Exactly what I was looking for

    I bought these for my teen during the last knix sale when the teen pairs were out of stock. I'm so glad that I did, my daughter loves them. She finds them comfortable and loves that she doesn't have to worry about leaks, especially for a girl who moves a lot in her sleep.

    Samantha
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    So Comfy

    Perfect cut for my body and butt.

    Lauren
  • Rated 5 out of 5 stars
    2 months ago
    Excellent customer service and follow up

    Customer service is always prompt and responsive to reasonable requests.

    CJ W.
    Verified Buyer