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Home / Teen Period Underwear / Teen Leakproof UltraThin No-Show Bikini 3-Pack
KnixTeen

Teen Leakproof UltraThin No-Show Bikini 3-Pack

$65.00 USD

$72.00

Save $7
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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

| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue

Absorbency: Moderate

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

Color: Strawberry Field/Sweet Tea/Baby Blue Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

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

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.
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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-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

| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue
| Strawberry Field/Sweet Tea/Baby Blue

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

Soft Top Layer

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

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Teen First Period Kit - Bikini

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4.4
Rated 4.4 out of 5 stars
Based on 683 reviews
Total 5 star reviews: 500 Total 4 star reviews: 74 Total 3 star reviews: 43 Total 2 star reviews: 28 Total 1 star reviews: 38
86%would recommend these products
ComfortRated 4.5 on a scale of 1 to 5
FitRated -0.2 on a scale of minus 2 to 2
EffectivenessRated 4.5 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)
683 reviews
  • Rated 5 out of 5 stars
    4 minutes ago
    Work great

    I bought these for my 12 year old daughter and she loves them. They fit great and have great absorbency.

    Michelle Y.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    7 hours ago
    Lifesaver

    Thin but well built. Gusset had adequate coverage for night and great for most period days.

    Hilary H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    JB

    These are super comfy and look great under clothes. No panty lines like other products I’ve tried. Really happy with them.

    Julie B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Great Item

    Comfortable. Beautiful. Knix items are top of the line Thank You

    Mary B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Leakproof underwear

    Great protection and they feel light and airy. Very comfortable.

    Tracey H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Comfy, Cute, and absorbent

    Love these! They feel comfy, fit me well and are great for my lighter days on my period.

    I will definitely be buying a few more soon.

    Thanks!

    Leah H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    SOOOO WORTH IT

    The best period underwear I’ll be buying more. I’m normally a size small and ordered a size small and it fit perfectly. I normally buy this as back-up for wearing a tampon but I wore this without a tampon or pad for a few hours and it did not leak at all.

    Katherine S.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    So good

    Wasn’t sure about these but so happy I have them a try !

    Marieve L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Quite Impressed

    My first time trying period underwear, and I thought these were great. No leaks and fairly comfortable. I’ve been thinking about buying them for a while and I’m glad I finally did.

    Nora H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Love

    I own 5 pairs now. My absolute favourite

    Hailey I.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    For Teen Daughter

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

    Erin W.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    Love these panties

    I ordered these in the cherry shimmer color and was worried that the color wouldn't match the red of the new Uplift Push-Up bra I ordered, but they are a great match. They fit true to size, and are very comfortable. I love Knix!

    Leanne M.
    Verified Buyer
    Was this helpful?