Leakproof UltraThin No-Show Underwear Bikini

Hanging out or running to your next class? These period undies provide the ultimate comfort you want, plus ultra-thin protection you need from sweat, discharge and leaks. It’s a classic silhouette made with a super soft-and-stretchy, quick-drying material. It absorbs about the equivalent of 2.5 super tampons for an extra dose of confidence on those medium-flow days.

Key Features:
- 360LeakSeal™ patented technology designed to seal in leaks from every angle
- Soft and stretchy for comfort throughout the day
- Seamless look for any OOTD
- Quick dry for that fresh feel

Kt period underwear and pads are now sales tax-free in Canada.* We celebrate improvements to the accessibility and affordability of essential period care products. Learn More.

more absorbent protection, without any extra bulk
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Image of a absorbancy surrounding text
Holds about 2.5 super tampons' worth of blood.
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Rapidly absorbs moisture to keep you fresh and dry all day.
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Allows air to circulate to keep you cool and dry.

Hanging out or running to your next class? These period undies provide the ultimate comfort you want, plus ultra-thin protection you need from sweat, discharge and leaks. It’s a classic silhouette made with a super soft-and-stretchy, quick-drying material. It absorbs about the equivalent of 2.5 super tampons for an extra dose of confidence on those medium-flow days.

Key Features:
- 360LeakSeal™ patented technology designed to seal in leaks from every angle
- Soft and stretchy for comfort throughout the day
- Seamless look for any OOTD
- Quick dry for that fresh feel

Kt period underwear and pads are now sales tax-free in Canada.* We celebrate improvements to the accessibility and affordability of essential period care products. Learn More.

Machine wash cold, do not bleach, do not iron, do not dry clean, lay flat to dry.

Body: 77% Nylon, 23% LYCRA® XTRA LIFE™Spandex;

Fresh Fix Technology®Gusset: Gusset 1: 86% Cotton, 10% Spandex, 4% Carbon; Gusset 2: 96% Polyester, 4% Spandex; Gusset 3: 83% Polyester, 11% Spandex, 6% Polyurethane

Additional Product Ingredient Information

For items with a 20% or more discount, you may exchange for another item or return for store credit. No refunds can be accommodated. 

Items marked as “Flash Sale” or “Clearance” are final sale, meaning no returns, exchanges or refunds can be accommodated. No exceptions. 

Please note: Sale items are not eligible for our First Pair Risk-Free Policy.

We offer free standard shipping on all orders over $80.

We ship our items via DHL or Canada Post depending on your location. Please allow 1-2 business days for your items to be processed and shipped. During high volume periods, your order may take up to 7 business days to dispatch from our warehouse location. 


Canadian Orders: 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.


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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Period underwear and pads are exempt from federal sales tax in Canada. They are also exempt from most provincial / harmonized sales taxes. But are subject to the following provincial sales tax rates which will apply to orders shipped to the following provinces and to orders purchased in retail stores located in the following provinces: British Columbia and Manitoba: 7% PST; Saskatchewan: 6% PST. 

Need more info? Click here

Each pair has a built-in liner that absorbs period blood. Kt Period Underwear is categorized by light, moderate and heavy flows so you can find the right pair for your teen’s needs.

Heavy Absorbency

Absorbs about the same as 3 super tampons. Perfect for overnight protection or your teens heaviest days when changing into a fresh pair might not be convenient.


Moderate Absorbency

Absorbs about 2.5 super tampons' worth of blood. Ideal for medium period days, discharge and sweat.


Light Absorbency

Absorbs about the same as about 1 regular tampon worth of blood, sweat or discharge. Ideal for lightest period days, spotting, sweat and discharge.

All of our period underwear, swimwear, reusable pads, and activewear have our patented leakproof technology built right in. Liner’s are discreet and comfortable, and fit for your teen’s unique flow. 

That’s up to your teen or tween! Every flow and comfort level is different.

Depending on the absorbency level of the period underwear and the heaviness of your teen’s flow, they can wear our period undies on their own or as a backup to tampons or menstrual cups. 

We always recommend they choose an option that makes them feel most confident!

Step 1: Give your teens underwear a quick rinse under cold water.

Step 2: Throw it in the washing machine with your regular clothes. Wash on cold with mild detergent (no softener or bleach).

Step 3: There are two ways to dry them depending on the undies you have: lay flat to dry for medium absorbency products, or tumble dry on low for high to super absorbency products.

Step 4: That’s it! No ironing needed.

Check out our size chart here. If you want some help, we have virtual fitters ready on deck to help you find your perfect fit. Book a video call with them today.

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 for 30 days!

If you ordered the wrong size of period underwear, we’ll send you a different pair at no cost or offer you a standard refund within 30 days of delivery (excluding original shipping fees).

If your order included multiple period underwear, open, wash, and wear one pair only. That way if you don’t love them, any unopened packages from the same purchase will be eligible for an exchange or standard refund (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 6 reviews
  • 5 Stars
    5 Reviews
  • 4 Stars
    0 Reviews
  • 3 Stars
    1 Review
  • 2 Stars
    0 Reviews
  • 1 Star
    0 Reviews
83% of reviewers would recommend this product to a friend
Quality
Rated 4 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
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Review posted
Reviewed by Sarvia B.
Verified Buyer
Pant Size
Kids 12-14
Size Purchased
XS
Usage
  • Primary Protection
Rated 5 out of 5

Great underwear

I have two girls that play sports and these are perfect for them. They don’t complain of any discomfort and best part…they wash very well! Highly recommend this product

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I recommend this product
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
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Review posted
Reviewed by Jolie G.
Verified Buyer
Pant Size
Kids 8-10
Size Purchased
XS
Usage
  • Period
Rated 5 out of 5

13 y.o. Approved

I purchased these in preparation. My daughter thinks these are comfy and are perfect for her to wear to school when she starts.

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I recommend this product
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
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Review posted
Reviewed by Clarissa S.
Verified Buyer
I'm a...
Parental Figure
I purchased for...
A Teenager/Tween
Pant Size
Kids 12-14
Size Purchased
S
Usage
  • Primary Protection
Rated 5 out of 5

Teen likes these

Very comfortable

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I recommend this product
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
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Review posted
Reviewed by Nelofer B.
Verified Buyer
I'm a...
Adult
I purchased for...
Myself
Pant Size
Teen 4-10
Size Purchased
S
Usage
  • Incontinence
Rated 5 out of 5

Will only wear KNIX

I wear light or medium absorbency everyday! They are very good quality and true to size!

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I recommend this product
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
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Review posted
Reviewed by Jessica M.
Verified Buyer
I'm a...
Adult
I purchased for...
A Teenager/Tween
Pant Size
Teen 18-20
Size Purchased
M
Usage
  • Back-up Protection
Rated 5 out of 5

My 12 year old loves these.

My daughter just started getting her period and was worried about leaks. She tends to wear these with a pad to ensure there are no embarrassing accidents at school or while out with friends.

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I recommend this product
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
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