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Home / Thong Underwear / Super Leakproof® No-Show Thong
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Super Leakproof® No-Show Thong

$29.00 USD

Mix & Match: 3+ for $25 each
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Absorbs about 4 super tampons

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Invisible under clothes

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Perfect for daily wear

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Machine washable

Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

| Black
Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

Ashley has 39” hips and wears KNIX S | Black

Ashley has 39” hips and wears KNIX S

| General

Ashley has 39” hips and wears KNIX S

Absorbency: Moderate

Moderate
Drop
Drop
Drop
Drop
Drop
about 2-4 super tampons
Essential
Drop
Drop
Drop
Drop
Drop
No Absorbency
Light
Drop
Drop
Drop
Drop
Drop
about 1-3 regular tampons

Color: Black

Size:

True to Size

•

Size:

Size and Fit Guide

Free Shipping on orders $100+

Shipping

Shipping
Processing Time

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* USD = Free standard Shipping (4-8 business days)**
Expedited = $4.99 USD (3-6 business days)**

Orders under $100* USD = $7.99 USD Standard Shipping (4-8 days)**
Expedited = $9.99 USD (3-6 business days)**

*After discounts, before shipping and taxes. Processing times not included in estimates.
**Military Addresses Excluded. Standard Military Address Shipping = $10.00 USD (est. varies per location)
Easy Exchanges within 30 Days

Returns

Returns

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.

Sale & Last Call

Items discounted below 30% are eligible for size exchange or store credit. Items discounted 30% and above are final sale – no refunds, store credits, or exchanges can be accommodated.
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"I genuinely thought my thong days on my period were over. But there I was, rocking my jeans with zero leaks, no worries, and full comfort and confidence."

- Glamour

Comfort-First Fit

Thong style with a mid-rise fit and minimal 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 4 super tampons worth of liquid—perfect for heavy flow days, overnight protection, and light bladder leaks.

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.

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Ashley has 39” hips and wears KNIX S | Black
| Black
Ashley has 39” hips and wears KNIX S | Black
Ashley has 39” hips and wears KNIX S | Black
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Everyday Wear
  • • No leakproof protection
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • heavy period days
  • • overnight protection
  • • light bladder leaks
  • 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

Drop
Drop
Drop
Drop
Drop
  • • light period days
  • • sweat
  • • discharge
  • tsp
    about 1-3 tsp
  • pad
    about 1-3 pantyliners
  • tampon
    about 1-3 regular tampons
  • cup
    about 0.5 menstrual cups

Moderate

Drop
Drop
Drop
Drop
Drop
  • • moderate period days
  • • light bladder leaks
  • • sweat
  • 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

Drop
Drop
Drop
Drop
Drop
  • • extra heavy period days
  • • overnight protection
  • • light bladder leaks
  • 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

Built-in protection that feels like nothing at all

Our original Fresh Fix Technology® features a built-in absorbent liner absorbing about 3-6 super tampons worth of liquid so you feel fresh and in-control.

Soft Top Layer

Soft Top Layer

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

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4.4
Rated 4.4 out of 5 stars
Based on 1,834 reviews
Total 5 star reviews: 1.3k Total 4 star reviews: 242 Total 3 star reviews: 107 Total 2 star reviews: 62 Total 1 star reviews: 92
89%would recommend these products
ComfortRated 4.4 on a scale of 1 to 5
EffectivenessRated 4.5 on a scale of 1 to 5
FitRated -0.1 on a scale of minus 2 to 2
Ease of UseRated 4.3 on a scale of 1 to 5
Write a Review (Opens in a new window)
1,834 reviews
  • Rated 5 out of 5 stars
    4 minutes ago
    Get them!

    I had been holding off on getting these because of the price. A friend told me about them because while we were playing a fun adult game of soccer I had tinkled a bit in my underwear:( I’m 42 and have given birth so things are not like they used to be.

    I bought 3 pairs and my period had started the day they were delivered. I figured I would try them out during my cycle because I hate wearing full bottom underwear. The thongs were amazing and I never leaked once! I ordered 4 more pairs during a Black Friday sale. After my menstrual cycle I played a game of coed flag football. I wore my Knix and was not worried at all! Just a little accidental urine and no leaking! I no longer have to worry or be embarrassed. Thank you Knix!

    Tara H.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    5 Stars

    Comfortable and truly outfit saving. Even wore under leggings and it wasn’t apparent they were any different than a normal pair.

    Elisa
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    5 Stars

    Comfortable and truly outfit saving. Even wore under leggings and it wasn’t apparent they were any different than a normal pair.

    Elisa
    Was this helpful?
  • Rated 5 out of 5 stars
    4 days ago
    5 Stars

    Love them

    Rochelle
    Was this helpful?
  • Rated 4 out of 5 stars
    5 days ago
    Great except the new sewn in tag

    I love all Knix underwear but I was surprised and not thrilled with new scratchy sewn in tags that I now have to cut out and risk ripping the seam. Why did that change?

    Jennifer R.
    Verified Buyer
    Was this helpful?
  • Rated 2 out of 5 stars
    1 week ago
    Poor fit

    I wish these fit. They are too big. Especially in the crotch gusset making them super uncomfortable. I wear a M but these are way to wide. Now I have $100+ in underwear that doesn't fit, and can't return because they've been washed.

    E
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Amazingly Leakproof!!

    I love allll my knix products and this Leakproof thong is perfect when you want to make sure your period underwear don't show through a cute outfit! 1000000/10 highly recommend!!!

    Lauren D.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    Super leakproof no show Thong

    The large size was too loose - size medium fits better - a tad tight.

    Sharon M.
    Verified Buyer
    Was this helpful?
  • Rated 3 out of 5 stars
    1 month ago
    Great product, but….

    I love Knix underwear, especially the thongs and bikini style. The only reason why I gave this a 3 star rating instead of 5 star is because even though I ordered the super leakproof I received medium leakproof instead.

    Cassandra F.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    2 years and counting

    I got my first few pairs of these undies about 2 years ago, out of about 10 pairs bought I’ve just thrown out 2 pairs for coming apart but I’ve worn them almost once a week, it’s more for ‘sneeze & pre’ situations for me over periods but they have been great for me and I’m reordering now!

    Sure would be nice to get a discount for repeat customers though!

    Denise D.
    Verified Buyer
    Was this helpful?
  • Rated 4 out of 5 stars
    1 month ago
    What happened to the beautiful colors?

    I am a 68 year-old woman that has been wearing you guys thongs for a while. When I click on the link to purchase more. Showing more beautiful colors until you go to the super leakproof there are only 5 basic colors to choose from. Please change this for medium as well as super.

    Berneta
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Where have you been all my life

    I can’t believe I’ve made it this far in life without them

    Sylvie D.
    Verified Buyer
    Was this helpful?