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Super Leakproof® Cotton Boxer Brief

$42.00 USD

Buy 3+ Save 15%, Buy 5+ Save 20%

Absorbs about 6 super tampons

Breathable cotton

More absorbency without bulk

Machine washable

| Pepper
| Pepper
| Pepper
| Pepper
| General

Color: Pepper

Size:

True to Size

Size:

Size and Fit Guide

Build Your 3-Pack

Super Leakproof® Cotton Boxer Brief

Color: Pepper

Size:

Size:

Super Leakproof® Cotton Boxer Brief

Color: Pepper

Size:

Size:

Super Leakproof® Cotton Boxer Brief

Color: Pepper

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 42 Points

Comfort-First Fit

Boxer shorts with a mid-to-high rise and maximum bum coverage.

Heavy Absorbency

Absorbs about 6 super tampons worth of liquid—great for heavy days or overnights.

Cozy Cotton-Blend

Soft cotton with a hint of spandex feels luxurious against your skin.

Worry-Free Protection

An innovative floating gusset provides leak protection from every angle.

Easy to Wash

Machine washable just like regular underwear.

Zoom

| Pepper
| Pepper
| Pepper
| Pepper
| 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
FRESH FIX TECHNOLOGY®

Cotton meets patented protection.

A sewn-in, floating liner soaks up about 6 super tampons’ worth of liquid—so you stay fresh, comfortable, and in control.

Soft Top Layer

Gently wicks away moisture to keep you fresh and odor-free.

3.7
Rated 3.7 out of 5 stars
Based on 14 reviews
Total 5 star reviews: 7 Total 4 star reviews: 1 Total 3 star reviews: 2 Total 2 star reviews: 3 Total 1 star reviews: 1
57%would recommend this product
FitRated 0.1 on a scale of minus 2 to 2
ComfortRated 3.9 on a scale of 1 to 5
EffectivenessRated 3.6 on a scale of 1 to 5
Ease of UseRated 3.4 on a scale of 1 to 5
14 reviews
  • Rated 5 out of 5 stars
    4 days ago
    Very comfortable

    When I got these, I thought they’d feel bulky, but they don’t at all! Very comfortable and stretchy.

    Camila H.
    Verified Buyer
  • Rated 5 out of 5 stars
    6 days ago
    First comfy panty I've been able to wear in a long time.

    They are just what I needed especially for sleep. They don't cut into your groin area and move around with your tossing and turning with getting your panties all bunched up! I just wish there were better colors. you can't wear this mulberry or the black under summer whites and pastels. We need beiges.

    Merilyn J.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    My first ever pair of period underwear

    And I love them. They're comfortable and the lining is soft. There was one seam in the gusset that I had to lay flat so it wouldn't bother me but that wasn't a problem.

    Rachel E.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    These were very comfortable, they had good stretch and didn't chafe or constrict anywhere.

    Courtney W.
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    the elastic edges were comfortable.

    ADDIE P.
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Comfortable and much coverage. No dig in and held up well after wash.

    LINDA K.
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    I was so pleasantly surprised that this underwear wasn't tight at first. I loved how it fit comfortably right away instead of having to wash and wear a few times before the fabric relaxes. It was perfect from first trying it on.

    Sarah P.
  • Rated 4 out of 5 stars
    1 month ago
    4 Stars

    I washed them once and everything felt fine, a bit of tightening after throwing them in the dryer but not uncomfortable and they stretched back out after wearing

    Kassandra L.
  • Rated 3 out of 5 stars
    2 weeks ago
    Some features I would change

    I'm glad they're cotton, the leg opening is more comfortable than the tighter materials.

    I wish the waistband had a nice wide band that lays flat, instead of the skinny elastic.

    I also wish the absorbent liner was sewn in down the sides of it, instead of just on the short ends. When I lay on my side, it can shift around.

    Alyssa D.
    Verified Buyer
  • Rated 3 out of 5 stars
    3 weeks ago
    3 Stars

    I dont love the padding in this one bc its kind of loose — not completely attached along the middle. Dont like the feeling of it moving around in there.

    Kelly
  • Rated 2 out of 5 stars
    5 days ago
    Meh

    Not that impressed with these underwear. The absorbency pad is not sewn in so it shifts around when you’re sleeping. The black pad at the back abruptly ends and there is this small flap seam flap that is also not sewn down and feels weird when wearing them. I just was expecting more from these and upon first trying them on they didn’t feel that great.

    Aj
    Verified Buyer
  • Rated 2 out of 5 stars
    6 days ago
    Leaked

    Pros: cotton is comfortable, leg openings weren’t overly tight like a lot of leakproof boxer briefs.

    Cons: coverage area is very narrow and short, and also moves around, they leaked very easily.

    Katie
    Verified Buyer

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