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KnixTeen

Teen Leakproof UltraThin No-Show Boyshort

$24.00 USD

Buy 3+ Save 15%, Buy 5+ Save 20%

Absorbs about 2.5 super tampons

Invisible under clothes

Superior protection without the bulk

Machine washable

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Color: Black

Size:

True to Size

Size:

Size and Fit Guide

Build Your 3-Pack

Teen Leakproof UltraThin No-Show Boyshort

Color: Black

Size:

Size:

Teen Leakproof UltraThin No-Show Boyshort

Color: Black

Size:

Size:

Teen Leakproof UltraThin No-Show Boyshort

Color: Black

Size:

Size:

Free Shipping on orders $100+

Shipping

Shipping

Processing Timelines

Please allow 1-2 business days for our warehouse team to pack and ship your order. During peak periods such as sales, holidays and product launches, please allow up to 4 business days for us to process your order. Once an order is placed, we cannot guarantee any address updates, order changes or cancellations. Orders placed on Friday after 1PM will not be shipped until the following Monday.


Split Shipments

Most orders will ship from a single warehouse. However, we occasionally ship from a combination of warehouse locations, so you may receive your order in multiple parts. If items from your order ship in separate packages, we’ll send you tracking information for each package when it becomes available.

Delivery Timelines

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines do not include processing times. See above for details. All transit times are measured in business days which are Monday-Friday, excluding holidays.

Please note, all shipping timelines are estimates and are not guaranteed.

We are not able to ship to US territories (including Puerto Rico, U.S. Virgin Islands, Guam, Northern Mariana Islands and American Samoa) at this time.

First Pair Risk Free for 30 Days

Leakproof Underwear, Risk Free

Returns & Exchanges

New to leakproof? Your first pair is risk free for 30 days. Wear them, wash them, and see how they work for your body. Not right for you? We'll refund the item price (original shipping excluded). Prefer a different size or style? We also offer free exchanges. Just email info@knix.com and we'll take care of you.

Purchased leakproof before? Within 30 days of delivery you can exchange for another size, style, or store credit. We're unable to provide refunds on underwear. If you ordered multiple pairs, please open, wash, and wear one pair only before initiating an exchange.

Still have questions? View our full policy here.

Rewards Members Earn 24 Points

Product Description

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.

Comfort-First Fit

Boyshort silhouette with a mid-rise fit and extra hip and bum coverage.

Worry-Free Protection

Our newest leakproof innovation provides more absorbency without the bulk. Patented 360 LeakSeal™ technology locks in leaks at every edge.

Moderate Absorbency

Absorbs 2.5 super tampons worth of liquid—perfect for moderate flow days, light bladder leaks, and sweat. The carbon cotton gusset top layer keeps you dry.

No-Show Style

Buttery-soft and smooth fabric gives a seamless look and feel. Disappears under clothes, even leggings.

Easy to Wash

Machine washable just like regular underwear.

Zoom

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How to Choose?

Essential

  • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

  • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
  • tsp
    about 8-14 tsp
  • pad
    about 1.5-3 regular pads
  • tampon
    about 4-7 super tampons
  • cup
    about 1.5-3 menstrual cups

Light

  • Daily freshness. For sweat, discharge, period spotting, or backup protection.
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

  • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
  • tsp
    about 4-8 tsp
  • pad
    about 1-1.5 regular pads
  • tampon
    about 2-4 super tampons
  • cup
    about 0.5-3 menstrual cups

Ultra

  • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
  • tsp
    about 15-20 tsp
  • pad
    about 1.5-2.5 super pads
  • tampon
    about 7-11 super tampons
  • cup
    about 2-3 menstrual cups
FRESH FIX TECHNOLOGY®

Built-in protection that feels like nothing at all.

Our patented 360 LeakSeal™ technology locks in leaks at every edge. The ultra-thin liner absorbs about 2.5 super tampons worth of liquid.

Soft Top Layer

Gently wicks away moisture while keeping you feeling fresh and odor-free.

4.6
Rated 4.6 out of 5 stars
Based on 33 reviews
Total 5 star reviews: 26 Total 4 star reviews: 4 Total 3 star reviews: 0 Total 2 star reviews: 3 Total 1 star reviews: 0
What our customers are saying
Customers say these boyshort-style underwear are exceptionally comfortable and fit well. Many reviews mention their suitability for active wear and sports. The lightweight, thin design gets frequent praise for being discreet under clothing. While most find them reliable, some users note concerns about breathability and occasional leaks. Parents frequently report their teens prefer these over traditional options, particularly appreciating the coverage and fit under uniforms. Common feedback highlights the accurate sizing guide and easy care routine.
91%would recommend this product
ComfortRated 4.8 on a scale of 1 to 5
FitRated 0.0 on a scale of minus 2 to 2
EffectivenessRated 4.7 on a scale of 1 to 5
Keywords
Keywords
Rating
Ratings
Height
Height
Usual Pant Size - Knixteen
Usual Pant Size - Knixteen
Size Purchased - Knixteen Underwear
Size Purchased - Knixteen Underwear
33 reviews
  • Rated 5 out of 5 stars
    6 days ago
    Perfect fit!

    Love love love Knix, especially the teen boyshorts!

    Amanda M.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    4 months ago
    My daughter loves them

    She loves them so much she asked to buy more for everyday wear. My only wish is that there was a label with absorbency level

    Samantha
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    7 months ago
    .

    .

    Lisa H.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    7 months ago
    Vert comfy

    My Daughter love it.

    Karine B.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    8 months ago
    Great! But please improve the labels.

    Super comfy, enjoyable to wear. But Knix, for the love of all that is holy, PLEASE find a way to label each pair with their absorbency level. It is downright mean to expect my hormone overloaded, cramping body to wake up and remember which pair of underwear has the right absorbency equivalent for the day. You've gotten them all down to such nice, light, non-bulky formats that it isn't obvious to my period-foggy brain which is which, and I feel like that's a pretty easy fix on your end. So please, help a girl out.

    Carlee F.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    10 months ago
    5 Stars

    They fit very well, and the size guide was very accurate! Super comfortable, hughly recommend!

    Stephanie
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    12 months ago
    They are amazing

    Picked these up for my niece and she loved them!

    Nicole k.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    1 year ago
    Leakproof underwear

    Perfect for every day wear.

    Comfortable.

    Carla C.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 4 out of 5 stars
    1 year ago
    Game changer

    My daughter loves these. They fit well, are comfortable (even during sports) and wash well. Going back to order more.

    Erin C.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    1 year ago
    Great product!

    My daughter loves this underwear and has no problem wearing them. Easy to wash and she says they are very comfortable :)

    jessica m.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 4 out of 5 stars
    1 year ago
    Underwear

    Love these boy short underware

    Bea B.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort
  • Rated 5 out of 5 stars
    1 year ago
    Favourite everyday of my teen

    My daughter only wears these underwear now. If she’s out, she does laundry. Great fit. Great function.

    Shar H.
    Verified Buyer
    Reviewing
    Teen Leakproof UltraThin No-Show Boyshort