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Home / Bikini Underwear / Super Leakproof Cotton Bikini
New

Super Leakproof Cotton Bikini

$29.00 USD

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

Absorbs about 6 super tampons

Breathable cotton

More absorbency without the bulk

Machine washable

Adecia has 40.5“ hips and wears KNIX M

Adecia has 40.5“ hips and wears KNIX M

Adecia has 40.5“ hips and wears KNIX M

Absorbency: Heavy

Color: Dusty Pink Limited Edition

Size:

True to Size

•

Size:

Size and Fit Guide

Build Your 3-Pack

Super Leakproof Cotton Bikini

Color: Dusty Pink Limited Edition

Size:

Size:

Super Leakproof Cotton Bikini

Color: Dusty Pink Limited Edition

Size:

Size:

Super Leakproof Cotton Bikini

Color: Dusty Pink Limited Edition

Size:

Size:

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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.
Easy Exchanges within 30 Days

Returns

Returns

Sale & Last Call

Items discounted 30% and below are eligible for size exchange or store credit. Items discounted above 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.

Free Returns

Knix covers the return shipping fees for exchanges and refunds initiated through our Return & Exchange Portal. Exchange orders initiated through our Return & Exchange portal are also eligible for free shipping within the USA and Canada. Please note, the shipping fees on your original order are non-refundable.

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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Comfort-First Fit

Bikini silhouette with a classic mid-rise fit and medium bum coverage.

Heavy Absorbency

Absorbs 6 super tampons worth of liquid—perfect for heavy flow days, overnight protection, and light bladder leaks.

Cozy Cotton-Blend

Soft cotton with a hint of spandex feels luxurious against your skin.

Worry-Free Protection

Innovative floating liner provides leak protection from every angle.

Easy to Wash

Machine washable just like regular underwear.

Zoom

| Dusty Pink
Adecia has 40.5“ hips and wears KNIX M | Dusty Pink
Adecia has 40.5“ hips and wears KNIX M | Dusty Pink
Adecia has 40.5“ hips and wears KNIX M | Dusty Pink
| 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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4.5
Rated 4.5 out of 5 stars
Based on 251 reviews
Total 5 star reviews: 190 Total 4 star reviews: 22 Total 3 star reviews: 15 Total 2 star reviews: 12 Total 1 star reviews: 12
85%would recommend these products
FitRated 0.0 on a scale of minus 2 to 2
ComfortRated 4.6 on a scale of 1 to 5
EffectivenessRated 4.5 on a scale of 1 to 5
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251 reviews
  • Rated 4 out of 5 stars
    38 minutes ago
    A little different

    These were a little different than any other Knix that I’ve gotten, where the liner part isn’t sewn in along the left and right sides (ie. It’s just sewn in at the front and back). That makes me feel a little less secure, but overall these are still comfortable and protective. And I got them at a great price on sale! Usually I wear a large and I got these in an xl because it’s all that was available, and while I will still get a large when available, the xl will work just fine in this case

    KU Profile picture for Knix US 2.0
    Knix US 2.0
    4 minutes ago

    Hey Laura!

    Thanks for the detailed review! We appreciate the feedback about the liner construction and are so glad you're still finding them comfortable and protective. Happy you scored a great sale price too!

    Team Knix

    Laura T.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 5 out of 5 stars
    2 weeks ago
    Love

    My daughter loves them. She said they are very comfortable

    Tihuana B.
    Verified Buyer
    Reviewing
    Teen Leakproof Cotton Bikini
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  • Rated 5 out of 5 stars
    3 weeks ago
    So soft and comfy

    I'm really gonna miss being able to get this style. The fabric was so much softer than the new cotton material and much more comfortable overall

    Jen C.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 5 out of 5 stars
    3 weeks ago
    Very soft

    Underwear were very comfortable and easy to wear!

    Dawn D.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 5 out of 5 stars
    3 weeks ago
    Great!

    My teen loves them. Very comfy and limit the pad usage, which is great.

    Erin N.
    Verified Buyer
    Reviewing
    Teen Leakproof Cotton Bikini
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  • Rated 5 out of 5 stars
    1 month ago
    Comfortable!

    This is my first time purchasing the cotton version ( I usually purchase the no show leakproof bikini) and I find them very comfortable, well made and I like that I can wear them for playing sports.

    Erin N.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 5 out of 5 stars
    1 month ago
    Love

    10/10

    Katey T.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 3 out of 5 stars
    3 months ago
    PSA on the liner!

    FYI, the liner on this style of underwear is not fully attached to the cotton outerlayer (ie: the pink part). In turn, the liner sometimes shifts, creating zones of "non-protection". I had to DIY sew the liner to the pink part so it wouldn't slip. Liner is leakproof like all of Knix's products, just be warned with this particular model. Lover of my other leakproof underwear from Knix!

    Jo
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 4 out of 5 stars
    3 months ago
    Comfortable!

    Great quality

    Debra H.
    Verified Buyer
    Reviewing
    Teen Leakproof Cotton Bikini Kit*
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  • Rated 5 out of 5 stars
    3 months ago
    Fits great

    Love the soft cotton material. Not bulky at all. Feels like regular underwear.

    Karen D.
    Verified Buyer
    Reviewing
    Teen Leakproof Cotton Bikini Kit*
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  • Rated 5 out of 5 stars
    3 months ago
    Comfortable

    These are very comfortable to wear

    Shawna G.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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  • Rated 5 out of 5 stars
    3 months ago
    Perfect!

    These are amazing. Very comfy while giving me peace of mind. I've been slowly replacing all of my regular underwear with Knix!

    Alisa R.
    Verified Buyer
    Reviewing
    Leakproof Cotton Bikini - Last Call
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