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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

Bundle & Save: 3 for $65
Checkmark

Absorbs about 2.5 super tampons

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Invisible under clothes

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Superior protection without the bulk

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Machine washable

Maya has 35

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

Maya has 35

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

Maya has 35

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

| General
| General
| General
| General
| General

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

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

Maya has 35

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

Size:

Size:

Maya has 35

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

Size:

Size:

Maya has 35

Teen Leakproof UltraThin No-Show Bikini

Color: Night Sky Limited Edition

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.

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 $100* CAD = Free Shipping (2-6 business days)

Orders under $100* 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

Leakproof Underwear, Risk Free
Trying leakproof underwear for the first time? Your first pair is completely risk free for 30 days. Wear them, wash them, and see how they work for your body. If they’re not right for you, we’ll refund your first pair. Prefer a different size or style? We also offer free exchanges.

How it works:

  • Risk free applies to leakproof underwear on your first order
  • Refund covers the item price (original shipping excluded)
  • Just email info@knix.com and we’ll take care of you

Return Policy
Return policy varies by product, please check if your item is refund or exchange eligible by viewing 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 regular underwear.

Zoom

Maya has 35
Maya has 35
Maya has 35
| General
| General
| General
| General
| General

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

Soft Top Layer

Gently wicks away moisture while keeping you feeling fresh and odor-free.
4.4
Rated 4.4 out of 5 stars
Based on 693 reviews
Total 5 star reviews: 504 Total 4 star reviews: 69 Total 3 star reviews: 46 Total 2 star reviews: 30 Total 1 star reviews: 44
85%would recommend these products
ComfortRated 4.6 on a scale of 1 to 5
FitRated -0.2 on a scale of minus 2 to 2
EffectivenessRated 4.6 on a scale of 1 to 5
Ease of UseRated 4.7 on a scale of 1 to 5
Write a Review (Opens in a new window)
693 reviews
  • Rated 5 out of 5 stars
    23 hours ago
    Amazing period underwear

    I use these as my primary period protection for my work day and they are awesome. Absorbent, no leakage on the sides like some other brands of period underwear, and they truly are no-show. I’ve worn them for a few months now and so far they are holding up well.

    Alexis S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    Yesterday
    So comfy!

    I have been converted! Tried these for the first time and honestly did not mind my period for once. I'm definitely getting more!

    Sian A.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 days ago
    Amazing

    I’m so impressed with this product for my daughter. It gives her more support and protection and more confidence through the day!

    Hannah B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    Amazing

    These feel amazing on and so far have done exactly what they are meant to do! They aren’t bulky or uncomfortable!

    Rachel C.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 days ago
    Leakproof UltraThin No-Show Bikini

    Very comfortable material and style.

    Caroline F.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    5 Stars

    My daughter loves the bathing suit

    Jeanine
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Perfect fit!

    Perfect fit, very comfortable! Love the bikini style is full coverage back.

    Karen B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Awesome

    The fit is excellent, the material is quality and the price is right!

    Hope D.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Super comfortable, highly recommend using these instead of pads

    I have been a pad user since the start but I always felt 'gross' on my period. I hated how bulky they felt and how they would shift sometimes. I feel so much more comfortable and confident wearing these. I love that I have a reusable method now and I am not contributing to the land fills in this small way. I can wear leggings on my period without worrying people can see I am wearing a pad.

    Andrea D.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Love the fit

    The fit is perfect, true to size. they are very comfortable and not bulky.

    Carol I.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Love

    Got these for my daughter who is 11 and started her period she loves them . Wish they had these when I was kid

    Coral E.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Amazing

    The new pair I got recently, the way the pads are sewn in are SO comfortable! These undies make me feel so much more secure with not only my period, but every day comfort! LOVE THESE!

    Megan H.
    Verified Buyer
    Was this helpful?

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