Leakproof Cotton Underwear Bikini

The comfiness of cotton, with the confidence of leakproof. Our newest floating liner tech sits comfortably on top of your undies to give extra protection from leaks, and is bonded at all the edges to trap in liquid absorbing the same as about 3 super tampons. You won’t notice the difference—other than the fact that your leak worries seem to float away.

Key Features:
- Cotton spandex blend for ultimate comfort
- Raised liner away from the body
- Bonded all around to help keep liquid in to prevent leaks
- Absorbs about the equivalent of 3 super tampons worth of period blood

soft and comfy underwear with innovative leak protection built in
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Holds about 3 super tampons' or 1.5 regular 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.
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Simply care with mild detergent and machine wash on cold.

The comfiness of cotton, with the confidence of leakproof. Our newest floating liner tech sits comfortably on top of your undies to give extra protection from leaks, and is bonded at all the edges to trap in liquid absorbing the same as about 3 super tampons. You won’t notice the difference—other than the fact that your leak worries seem to float away.

Key Features:
- Cotton spandex blend for ultimate comfort
- Raised liner away from the body
- Bonded all around to help keep liquid in to prevent leaks
- Absorbs about the equivalent of 3 super tampons worth of period blood

Machine wash cold, do not bleach, do not iron, do not dry clean, tumble dry low, wash with like colors.

Body: 96% Cotton/Coton, 4% Spandex

Fresh Fix Technology® Gusset: Gusset 1: 92% Polyester, 8% Spandex; Gusset 2: 95% Polyester, 5% Spandex; Gusset 3: 100% Polyester; 100% Thermoplastic Polyurethane 

Additional Product Ingredient Information

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! Learn more about our First Pair Risk-Free Policy.

For items with a 20% or more discount you may exchange for another item or store credit within 30 days of delivery. No refunds.


We offer free standard shipping on all orders over $70. 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.

US Orders: Please allow 3–10 business days for orders to arrive. 

International Orders: Please allow 10–25 business days for orders to arrive.  

NOTE: Orders placed on Friday after 1 PM will not be processed until the following Monday.   

CANADIAN CUSTOMERS: Shop www.knixteen.ca to order in Canadian currency.

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nothing is tmi here—we promise.
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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.


Medium Absorbency

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


Lightest 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.

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

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 your teen find their 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 your teen can try their 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.

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Sustainable
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Absorbent
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Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Image of a chrome heart surrounding text
Comfortable
Image of a chrome heart surrounding text
Sustainable
Image of a chrome heart surrounding text
Absorbent
Reviews
average rating 4.4 out of 5
Based on 5 reviews
  • 5 Stars
    3 Reviews
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    1 Review
  • 3 Stars
    1 Review
  • 2 Stars
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    0 Reviews
80% of reviewers would recommend this product to a friend
Quality
Rated 4 out of 5
Comfort
Rated 3 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
Review posted
Reviewed by Rocio P.
Verified Buyer
Rated 5 out of 5

Teen bikini

Love my teens bikini ultra leakproof.

Working great, very confortable

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Reviewed by Joy R B.
Verified Buyer
Rated 5 out of 5

Excellent

Amazing fit, comfort, coverage and protection

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Review posted
Reviewed by Sunita M.
Verified Buyer
I'm a...
Adult
I purchased for...
Myself
Pant Size
Teen 18-20
Size Purchased
XL
Usage
  • Back-up Protection
  • Period
Rated 5 out of 5

Like it

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 carla
Verified Buyer
Rated 4 out of 5

Comfortable

Comfy underwear!

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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 3 out of 5

Okay but not great.

My teen refuses to wear these.

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Quality
Rated 4 out of 5
Comfort
Rated 1 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
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