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Home / Teen Period Underwear / Teen Leakproof UltraThin No-Show Bikini
Best Seller

Teen Leakproof UltraThin No-Show Bikini

$25.00 CAD

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

Absorbs about 2.5 super tampons

Invisible under clothes

Superior protection without the bulk

Machine washable

Front view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Maya has 35" hips and is wearing a teen size M

Front view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Maya has 35" hips and is wearing a teen size M

Back view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Maya has 35" hips and is wearing a teen size M

On image text: Seamless look

Maya has 35" hips and is wearing a teen size M

Absorbency: Moderate

Moderate
about 2-4 super tampons
Light
about 1-3 regular tampons
Heavy
about 4-7 super tampons
Ultra
about 7-11 super tampons

Color: Night Sky Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*

Build Your 3-Pack

Front view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

Size:

Size:

Front view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

Size:

Size:

Front view of model wearing the Teen Leakproof UltraThin No-Show Bikini highlighting the coverage and smooth fit

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

Size:

Size:

Free Shipping on orders $125+

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.

Delivery Time

For the most up-to-date delivery time estimates, please refer to the shipping timeline at checkout. Delivery timelines vary depending on location and do not include processing times.

Shipping Charges

Orders over $125* CAD = Free Shipping (2-6 business days)

Orders under $125* CAD = $12 CAD Shipping (1-3 business days)

Orders delivering to NWT, Nunavut and Yukon are subject to $20 delivery fee.

*After discounts, before shipping and taxes.
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 25 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

Bikini silhouette with a classic mid-rise fit, medium 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 More Panty Lines

Made from our signature buttery-soft fabric and designed to be invisible under clothes, including leggings.

Easy to Wash

Machine washable, just like your regular underwear.

Zoom

Maya has 35
Maya has 35
Maya has 35

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

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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.
4.9
Rated 4.9 out of 5 stars
Based on 34 reviews
100%would recommend this product
ComfortRated 4.9 on a scale of 1 to 5
FitRated 0.0 on a scale of minus 2 to 2
EffectivenessRated 4.9 on a scale of 1 to 5
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34 reviews
  • Rated 5 out of 5 stars
    1 week ago
    Teen Found these to be sufficient

    Teen daughter, 4’11 80lbs prefers size xs or s

    She found the bikini style to be the most comfortable. Also enjoyed the nighttime shorts

    BG
    Bridget G.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    Sleek!

    My girls LOVE these no-show undies! They like the feel and that they aren't bulky at all. They work well and keep my girls feeling confident and comfortable.

    JD
    Julie D.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 months ago
    great

    perfect

    JL
    Julie L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    5 months ago
    Happy Satisfied Customer!

    Bought these for my daughter - they are great; she loves them! Comfortable and effective product.

    Thank you!

    WW
    Wendy W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    7 months ago
    For Teen Daughter

    She loves these over any other period underwear. Will only wear these!

    EW
    Erin W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    9 months ago
    Great so far!

    Bought these for my teenage daughter. So far so good!

    MH
    MELANIE H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    9 months ago
    Great

    These are great, very thin and comfortable. Don't forget they are teen size, so they run smaller than regular women's size. Make sure to check size chart.

    CB
    Chantal B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    10 months ago
    Daughter loves them!

    My daughter is 16 and loves these undies. They are super comfortable and provide added confidence throughout the day. She wears them daily and doesn’t wait for her menstrual cycle.

    SS
    Sandra S. I.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    10 months ago
    Great product

    Perfect for my tween!

    ER
    Emily R.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    11 months ago
    Great leakproof underwear

    Fit great under a dance costume and provided excellent protection from leakage

    MA
    Michele A.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    11 months ago
    So comfy

    I bought these for my 13 year old. She said they are so comfortable and just what she was looking for. She had tried a different brand first, and although they got the job done, she said these were just like wearing regular underwear and felt less like a diaper. We will be purchasing more!

    KF
    Kelly F.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 year ago
    Great!

    These are great for my teen who is a dancer. She loves them under her bodysuit and they are actually no-show which is amazing!

    MB
    Megan B.
    Verified Buyer
    Was this helpful?

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