Light Leakproof No-Show Underwear Boyshort

These period undies protect teens against leaks, sweat, and discharge. A classic silhouette made from soft, stretchy, quick-drying fabric with a thin liner that absorbs the same as about 1 regular tampon. Wear them as everyday underwear, as full protection on light days, or backup on heavy days.

Key Features:

- Quick-Drying

- Moisture and Sweat Wicking

- Absorbs the same as about 1 regular pantyliner/tampon

- Super soft & stretchy

- Invisible under leggings or shorts (aka no visible seam lines)

- Patented leakproof technology

made for doing everything or nothing on your period. your pick.
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Each pair holds the same as about 1 regular tampons worth of blood, sweat or discharge.
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Rapidly absorbs moisture to keep you fresh and dry all day.
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Thin, subtle, and designed to feel just like regular underwear.
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Simply care with mild detergent and machine wash on cold.

These period undies protect teens against leaks, sweat, and discharge. A classic silhouette made from soft, stretchy, quick-drying fabric with a thin liner that absorbs the same as about 1 regular tampon. Wear them as everyday underwear, as full protection on light days, or backup on heavy days.

Key Features:

- Quick-Drying

- Moisture and Sweat Wicking

- Absorbs the same as about 1 regular pantyliner/tampon

- Super soft & stretchy

- Invisible under leggings or shorts (aka no visible seam lines)

- Patented leakproof technology

Machine wash cold with mild detergent, do not bleach, lay flat to dry.


Body: 77% Nylon, 23% Xtra Life Lycra 

Lining: 86% Cotton, 10% Spandex, 4% Carbon 

Gusset: Fresh Fix Technology® 


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 $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 4.6 out of 5
Based on 177 reviews
  • 5 Stars
    143 Reviews
  • 4 Stars
    16 Reviews
  • 3 Stars
    11 Reviews
  • 2 Stars
    1 Review
  • 1 Star
    6 Reviews
91% 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
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
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Review posted
Reviewed by C G.
Verified Buyer
Light Leakproof No-Show Underwear Boyshort
Reviewing
Light Leakproof No-Show Underwear Boyshort
I'm a...
Adult
I purchased for...
Myself
Pant Size
Teen 12-16
Size Purchased
M
Usage
  • Back-up Protection
Rated 5 out of 5

Extreme comfort

This was my first pair of Knix underwear and when trying them on for the first time, the fit was perfect and the comfort level was amazing!

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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 4 out of 5
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Review posted
Reviewed by Kathryn F.
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Light Leakproof No-Show Underwear Boyshort
Reviewing
Light Leakproof No-Show Underwear Boyshort
Pant Size
Teen 00-2
Size Purchased
S
Usage
  • Period
  • Primary Protection
Rated 5 out of 5

These feel like normal umderwear

Great product! Better than others we have tried!

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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
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
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Reviewed by Shelby
Light Leakproof No-Show Underwear Boyshort
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Light Leakproof No-Show Underwear Boyshort
Rated 5 out of 5

5 Stars

Love these cool designs as adult. Perfect for their day flow

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Reviewed by Shelby
(closed) Light Leakproof No-Show Underwear Boyshort - Clearance
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(closed) Light Leakproof No-Show Underwear Boyshort - Clearance
Rated 5 out of 5

5 Stars

Love these! As an adult I go up a size and they fit perfectly ! For First day flow

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Reviewed by Suzanne D.
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Light Leakproof No-Show Underwear Boyshort
Reviewing
Light Leakproof No-Show Underwear Boyshort
I'm a...
Adult
I purchased for...
A Teenager/Tween
Pant Size
Kids 12-14
Size Purchased
M
Usage
  • Back-up Protection
Rated 5 out of 5

Light leakproof no show underwear boy short

My granddaughter loves these

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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
Fit
Rated 0 on a scale of minus 2 to 2, where minus 2 is Runs Small, 0 is True to Size and 2 is Runs Large
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