Cotton Modal Super Leakproof Bikini

A highly absorbent bikini in modal, an eco-friendly fabric made from regenerative plants. Built with our patented, 3-layer leakproof technology built in.   

First layer: Moisture-wicking, antimicrobial technology wicks away sweat and moisture while neutralizing odors to keep you fresh all day long. 

Second layer: A super thin, highly-absorbent liner that holds the power of 8 tampons.

Third layer: A secure, liquid-resistant outer layer keeps leaks from happening.

it doesn’t get any softer than this.
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Image of a absorbancy surrounding text
Holds up to 8 tampons or pads worth of blood.
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Allows air to circulate to keep you cool and dry.
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Texture feels smooth against the skin for added comfort.
Antimicrobial layer kills bacteria and neutralizes smells.

A highly absorbent bikini in modal, an eco-friendly fabric made from regenerative plants. Built with our patented, 3-layer leakproof technology built in.   

First layer: Moisture-wicking, antimicrobial technology wicks away sweat and moisture while neutralizing odors to keep you fresh all day long. 

Second layer: A super thin, highly-absorbent liner that holds the power of 8 tampons.

Third layer: A secure, liquid-resistant outer layer keeps leaks from happening.

Main Body: 47% Cotton, 47% Modal, 6% Spandex 

Gusset Top Layer (Moisture Wicking + Anti-Odor): 84% Modal 8% Seaweed 8% Spandex 

Gusset 2nd Layer (Absorbent Fabric): 100% Polyester 

Gusset 3rd Layer Fresh Fix Technology 

Gusset 4th Layer (Waterproof Membrane): Polyurethane Film   

Free from PFAS and other chemical treatments. 

Machine wash cold with mild detergent, do not bleach, tumble dry on low.

Because they’re, well, underwear—we can’t accept exchanges or returns on used items BUT you can try your first-pair on your first order, risk-free!  

What's First-Pair Risk-Free?  

If your first order includes multiple period underwear: OPEN, WASH & WEAR ONE PAIR ONLY to test them out. That way, in the unlikely event that you don’t love them, any unopened packages from the same purchase can be exchanged or refunded back to you within 30 days of delivery (excluding original shipping fees).  All unopened packages will be donated to local organizations to support people in need.

We ship our items via DHL, or Canada Post depending on your location. Please allow 1-2 business days for your order to dispatch.  

For orders to Canada please allow 2-4 business days for shipping to the GTA, 3 - 10 business days for urban areas, and 6-15 business days for remote locations.  

Please note: orders placed on Friday after 1 pm will not be processed until the following Monday.  

FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
FOR THIS GENERATION
FOR THE PLANET
FOR REAL LIFE
nothing is tmi here—we promise.
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Super Absorbency

Absorbs up to 12 tsp (60 ml) of blood—that’s about 12 regular tampons or pads! Perfect for overnight protection or on your heaviest days when changing into a fresh pair might not be convenient.

High Absorbency

Absorbs up to 4-8 tsp (20-40 ml) of blood or the equivalent of 4-8 tampons or pads. These are perfect for heavy flow days.

 Medium Absorbency

These absorb approximately 3 tsp (15 ml) or about 3 tampons or pads worth of blood! Ideal for light to medium flow days or as backup to tampons or period cups.


All of our Period Underwear, Swim, and Activewear have our patented, 3-layer leakproof technology built right in—

First layer: Moisture-wicking, antimicrobial technology wicks away sweat and moisture while neutralizing odors to keep you fresh all day long. 

Second layer: A super thin, highly-absorbent liner that holds the power of 3-12 tampons or pads.

Third layer: A secure, liquid-resistant outer layer keeps leaks from happening. 

The short answer: Nope! Depending on the level of absorbency of leakproof period underwear you choose and the heaviness of your flow, you can wear our period undies on their own or as backup protection along with a pad or tampon. You're totally protected with our high and super absorbency leakproof underwear, while our low and medium absorbency leakproof underwear can replace pads and tampons on lighter days and work great as a backup to whatever you’re already using on heavier days.

Do a quick rinse before you throw your underwear in the machine. Wash on cold with mild detergent then tumble dry on low. That's it! Be sure not to use softener or bleach and never iron...not that you would.

If you’re not sure which size underwear to get, just book a Virtual Fitting and someone from the Knix team will video chat you to walk you through everything!

Because they’re, well, underwear—we can’t accept exchanges or returns on used items BUT you can try your first-pair on your first order, risk-free!  

How it works:

If your first order includes multiple period underwear: OPEN, WASH & WEAR ONE PAIR ONLY to test them out. That way, in the unlikely event that you don’t love them, any unopened packages from the same purchase can be exchanged or refunded back to you within 30 days of delivery (excluding original shipping fees).

 All unopened packages will be donated to local organizations to support people in need.



COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
COMFORTABLE
ABSORBENT
JUST PLAIN BETTER
REUSABLE
Reviews
average rating 4.7 out of 5
Based on 72 reviews
  • 5 Stars
    56 Reviews
  • 4 Stars
    10 Reviews
  • 3 Stars
    4 Reviews
  • 2 Stars
    2 Reviews
  • 1 Star
    0 Reviews
96% of reviewers would recommend this product to a friend
Quality
Rated 4 out of 5
Comfort
Rated 4 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 4 out of 5
72 Reviews
Reviewed by Stacie N.
Verified Buyer
I recommend this product
I'm A...
Parental Figure
I purchased for...
A Teenager/Tween
Pant Size
Teen 4-10
Size Purchased
L
Usage
  • Primary Protection
Rated 5 out of 5
Review posted

Great product

My daughter loves the feel of these panties. She wants nothing to do with pads so they are perfect. No leaks and they last the entire school day.

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Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 5 out of 5
Was this helpful?
Reviewed by Maesen
Verified Buyer
I recommend this product
I'm a...
Teenager
I purchased for...
Myself
Pant Size
Kids 12-14
Size Purchased
M
Usage
  • Period
  • Primary Protection
Rated 5 out of 5
Review posted

So Comfortable!

I always hated wearing pads, they just felt so yucky and wet. I never wanted to use tampons either. I saw these, and at first I thought that they were too expensive, but once I got them I realized they were worth every penny. They are so comfortable, and so thin yet still super absorbent! They felt dry and clean all the time while wearing these. I definitely recommend them!

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Quality
Rated 4 out of 5
Comfort
Rated 5 out of 5
Sizing
Rated 1 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 5 out of 5
Was this helpful?
Reviewed by Marie J.
Verified Buyer
I recommend this product
I'm a...
Parental Figure
I purchased for...
Myself
Pant Size
Teen 12-16
Size Purchased
XL
Usage
  • Primary Protection
  • Period
Rated 5 out of 5
Review posted

Love it!!!

Love my new Cotton Modal Super Leak underwear. I couldn’t believe how effective they are. I was able to wear them from 6-8 hours on my heavy days. I bought this

For my self, and I’m 41! I love everything about it! And I need more.

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Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 5 out of 5
Was this helpful?
Reviewed by Marnee M.
Verified Buyer
I recommend this product
I'm a...
Parental Figure
I purchased for...
A Teenager/Tween
Pant Size
Kids 12-14
Size Purchased
M
Usage
  • Primary Protection
Rated 5 out of 5
Review posted

Better than the original.

My daughter didn't want to try these but I bought some just to see what they felt like, turns out she LOVES them more than the originals. The fabric is so soft and they absorb so much. They fit her tween body just right and are true to size. I wish I had these when I was a tween.

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Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 5 out of 5
Was this helpful?
Reviewed by Michele H.
Verified Buyer
I recommend this product
I'm A...
Parental Figure
I purchased for...
Myself
Pant Size
Teen 18-20
Size Purchased
XXL
Usage
  • Primary Protection
  • Period
Rated 4 out of 5
Review posted

Comfortable protection

I am a larger woman, so the leakage protection did not protect me far enough back, however the middle area was well-protected and had no leaks for an 8-hour medium flow day

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Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Sizing
Rated 0 on a scale of minus 2 to 2, where minus 2 is Fits Small, 0 is True to Size and 2 is Fits Large
Effectiveness
Rated 4 out of 5
Was this helpful?