Leakproof Underwear Boyshort

Stretchy, seamless boyshorts with added coverage, featuring 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 3 tampons.

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

made for doing everything or nothing on your period. your pick.
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Holds up to 3 tampons or pads worth of blood.
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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.
Antimicrobial layer kills bacteria and neutralizes smells.

Stretchy, seamless boyshorts with added coverage, featuring 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 3 tampons.

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

Body: 77% Nylon, 23% LYCRA® 

Gusset Liner: 86% Cotton, 10% Spandex, 4% Carbon 

Gusset: Leakproof Technology   

Free from PFAS and other chemical treatments. 

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

We’ve extended our First Pair Risk-Free Policy* to give everyone a chance to try our new sizes. So even if it’s not your first order with Kt, you can return or exchange your period underwear until March 31, 2022. 

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. 

*Policy does not apply to sale or last call items.

We offer free 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.


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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Super Absorbency

Absorbs 9–12 tsp (45–60 ml) of blood—that’s about 9–12 regular tampons or pads! Perfect for overnight protection or your heaviest days when changing into a fresh pair might not be convenient.


High Absorbency

Absorbs 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

Absorbs up to 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, swimwear, reusable pads, 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 3–20 tampons or pads.

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

The short answer: nope! Depending on the absorbency level of your period underwear and the heaviness of your flow, you can wear our period undies on their own or as a backup to pads, tampons, or menstrual cups. You can wear our High and Super absorbency underwear alone and be totally protected, while our Medium absorbency underwear can be worn alone on lighter days or as backup on heavier days.

Step 1: Give your 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.

We’ve extended our First Pair Risk-Free Policy* to give everyone a chance to try our new sizes. So even if it’s not your first order with Kt, you can return or exchange your period underwear until March 31, 2022.

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.

*Policy does not apply to sale or last call items.

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 4.8 out of 5
Based on 822 reviews
  • 5 Stars
    678 Reviews
  • 4 Stars
    112 Reviews
  • 3 Stars
    16 Reviews
  • 2 Stars
    8 Reviews
  • 1 Star
    8 Reviews
97% 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
822 Reviews
Reviewed by Kayla M.
Verified Reviewer
Leakproof Boyshort
Reviewing
Leakproof Boyshort
I recommend this product
Rated 5 out of 5
Review posted

A REVIEW FROM AN 11 YEAR OLD

Hey! I'm Kayla and I'm 11! My mom is a nurse and wanted me to be prepared to have my first period, so she got me these. (Bikini's but now I wear boyshorts) This was a lifesaver! I have my period at school and I didn't know and when I went to the bathroom I was able to put on a pad! It saved me from leaking and getting blood all over. It's super comfy and it is very stretchy and breathable. The packaging is also a pencil case, makeup bag etc. It can also be used as a heating pad and comes with cute stickers. You put hot damp/wet face towels and it stays hot for a long time! The heating pad works very well! I would highly recommend these to everyone! There are literally no downsides.

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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 Allayna W.
Verified Buyer
Leakproof Boyshort
Reviewing
Leakproof Boyshort
I recommend this product
Rated 4 out of 5
Review posted

Good quality

I tried the Knixteen line after finding the women's sizing to be a touch too large for my frame.

Ordered a size L in these and they fit much better. I prefer the overall style of the bikini-type bottoms better but in terms of fit, these are far superior. I actually find that these boyshorts fit snugly and don't move around, which is exactly what one wants with period underwear!

For reference I'm 5'3 and about 125 pounds. If you have a small frame, go for either a size Large or even a Medium in the Knixteen line if you find the regular sizes a touch too large!

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Fit
Rated 1 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 Donna H.
Verified Buyer
Leakproof Boyshort
Reviewing
Leakproof Boyshort
I recommend this product
Rated 5 out of 5
Review posted

Great product

I have 12 year old twins. One loves these boy shorts, but she has heavy periods, so wears a pad with them. The other is very petite and live the bikini. She has light periods, so the bikini ones are perfect for her without a pad.

I highly recommend!! I will add, they run pretty small. My bigger gal wears a woman’s size 6 and the boy shorts in large are perfect. My petite size 10 in kids clothes wears the medium bikini, but can also wear the large in a pinch.

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Fit
Rated -2 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 Alyssa
Verified Buyer
Leakproof Boyshort
Reviewing
Leakproof Boyshort
I recommend this product
Rated 5 out of 5
Review posted

Great for Menstrual Cup Users!

I am a woman in my 30s, and find these to be SO helpful! I changed over to a menstrual cup a few years ago due to my concern about environmental waste. But i was still encountering issues with leakage on my heaviest days, and was annoyed I still had to purchase pantyliners in addition to using the cup. No more with these boyshorts and bikinis! I have removed that extra waste from my life, and feel confident and protected when wearing these at work during my heaviest days now! Game changer!!!

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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 Nguyen
Verified Buyer
Leakproof Boyshort
Reviewing
Leakproof Boyshort
Rated 3 out of 5
Review posted

Sizing guide could be more helpful

I am 87 lb 4'9" adult. My hip measurement is 24 / 25 so I ordered 2 of the boybriefs in small. The fit is very tight on thighs and butt so that my circulation feels cut off making them impractical for exercise. They are thin and otherwise look amazing. Haven't had the chance to bleed in them. Was excited that there is Knixteen since regular Knix sizing is too large for me but I wish the sizing chart accounted for more body types such as curvy and athletic. I've already spent $30+ and have nothing I can use.

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