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SuperPlus Leakproof® No-Show Bikini

$36.00 USD

Mix, Match & Save: 3+ for $33 each
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Absorbs 7-11 super tampons

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Front-to-back liner

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Bonded seams prevent leaks

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Machine washable

Shivani has 40” hips and wears KNIX L | Black

Shivani has 40” hips and wears KNIX L

| Black
Shivani has 40” hips and wears KNIX L | Black

Shivani has 40” hips and wears KNIX L

Shivani has 40” hips and wears KNIX L | Black

Shivani has 40” hips and wears KNIX L

| General

Shivani has 40” hips and wears KNIX L

Color: Black

Size:

True to Size

Size:

Size and Fit Guide

Build Your 3-Pack

Shivani has 40” hips and wears KNIX L | Black

SuperPlus Leakproof® No-Show Bikini

Color: Black

Size:

Size:

Shivani has 40” hips and wears KNIX L | Black

SuperPlus Leakproof® No-Show Bikini

Color: Black

Size:

Size:

Shivani has 40” hips and wears KNIX L | Black

SuperPlus Leakproof® No-Show Bikini

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

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 36 Points

Product Description

The most absorbent invisible period panty ever made. The Knix SuperPlus Leakproof No-Show Bikini is engineered for your heaviest days, absorbing an incredible 7 to 11 super tampons’ worth of flow. Despite its massive capacity, the seamless, raw-cut edges ensure it stays completely invisible under your tightest leggings or skirts. Featuring an extra-long gusset for 360-degree security, it’s the best high-absorbency no-show underwear for those who need maximum protection without the bulk.

Comfort-First Fit

Classic mid-rise bikini silhouette with medium coverage for hips and bum.

Ultimate Leakproof Protection

Our longest, most absorbent liner ever—front-to-back coverage without the bulk.

Day & Night Comfort

Buttery-soft stretch fabric moves with you, while bonded seams keep leaks contained and create a smooth, seamless look under clothing.

Machine Washable

Wash just like your regular underwear—easy, everyday care.

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Shivani has 40” hips and wears KNIX L | Black
| Black
Shivani has 40” hips and wears KNIX L | Black
Shivani has 40” hips and wears KNIX L | Black
| 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
PATENTED LEAKPROOF TECHNOLOGY

Our longest, most absorbent liner—ever.

Our original Fresh Fix Technology® features a built-in absorbent liner that soaks up about 7–11 super tampons’ worth of liquid—so you stay fresh, comfortable, and in control.

Soft Top Layer

Soft Top Layer

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

4.5
Rated 4.5 out of 5 stars
Based on 29 reviews
Total 5 star reviews: 24 Total 4 star reviews: 1 Total 3 star reviews: 1 Total 2 star reviews: 0 Total 1 star reviews: 3
86%would recommend this product
FitRated -0.1 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
Ease of UseRated 4.8 on a scale of 1 to 5
29 reviews
  • Rated 5 out of 5 stars
    3 minutes ago
    Best for postpartum exercise

    I bought these after going for a jog 6 months postpartum, and well we all know what happened! These are great for small leaks, no fear of running or jumping anymore! They aren’t too bulky either, no more noticeable under leggings than regular underwear. A must have for any active new mom!

    Stephanie
    Verified Reviewer
  • Rated 5 out of 5 stars
    4 days ago
    Comfy

    Bought for postpartum, I still used pads while dealing with the postpartum part but made life much easier when out and about, didn’t have to worry at all about any sort of leak! I’m plus size and found the disposable underwear very uncomfy and was very happy I chose to buy these, made me so much comfier and gave me a little normalcy in the chaos that followed birth… in future I would keep a couple pairs in the diaper bag just incase you end up needing to change plans last minute

    Jen
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Held Very Well

    It was so much better than I had expected it to be and held so much more than I thought. This is my first time trying period underwear and so far I really love them.

    J
    Verified Buyer
  • Rated 5 out of 5 stars
    1 week ago
    Love it!

    Purchased for my daughter. She says they are more comfortable than other brands that pinch at her waist. She feels confident wearing them to school.

    Stacie N.
    Verified Buyer
  • Rated 5 out of 5 stars
    2 weeks ago
    Great fit and comfort

    They work well for bladder issue. I would like to get several more

    Tony H.
    Verified Buyer
  • Rated 5 out of 5 stars
    2 weeks ago
    Honestly life changing

    I bought these "off brand" and as a last hope. You see, I was 20+ weeks pregnant and suffering from very painful vulvular varicosity. It was difficult to walk at the end of the day the pain was so bad. The "devices" meant to treat this condition are not only expensive, but very impractical for someone using the bathroom every hour (lots of velcro). I knew I needed support and I was hoping Knix would provide enough to make the remainder of my pregnancy bearable. I figured even if they didn't work, I would be able to use them postpartum and beyond so I took a chance. I am so glad I did. My daily quality of life has improved so much. I am no longer in pain and it is all thanks to Knix. I am so happy with my outcome I have passed the information onto my OBGYN in hopes that these can help other women in my situation.

    Megan B.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Comfortable and confident

    Super comfortable and cute, I love this as my period wear and they make me feel confident about not leaking throughout the day or night. They are also not as bulky as other period underwear I have tried which is also so nice to not feel like you are wearing a diaper that can be seen sticking out of your pants.

    Kally P.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Leakproof

    Excellent product

    Susan S.
    Verified Buyer
  • Rated 5 out of 5 stars
    3 weeks ago
    Best way to feel confident

    Comfortable fit, stays in place and stops embarrassing leaks

    Victoria R.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Super plus

    Wonderful product.

    Paige B.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Awesome

    Love them !!!

    Marie-Eve P.
    Verified Buyer
  • Rated 5 out of 5 stars
    1 month ago
    Love my Leakproofs

    I really like them. They aren't bulky and the fabric is very silky.

    Susan A.
    Verified Buyer