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Home / Thong Underwear / Light Leakproof UltraThin No-Show Thong
Best Seller

Light Leakproof UltraThin No-Show Thong

$27.00 CAD

Mix, Match & Save: 3+ for $20 each
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Absorbs about 2 regular tampons

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Invisible under clothes

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More absorbency without bulk

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Machine washable

Isabelle has 40” hips and wears a Knix size M | Sola

Isabelle has 40” hips and wears a Knix size M

Isabelle has 40” hips and wears a Knix size M | Sola

Isabelle has 40” hips and wears a Knix size M

Isabelle has 40” hips and wears a Knix size M | Sola

Isabelle has 40” hips and wears a Knix size M

| General
| General
| General
| General

Isabelle has 40” hips and wears a Knix size M

Absorbency: Light

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

Color: Sola

Size:

True to Size

•

Size:

Size and Fit Guide

Leakproof Underwear is Sales Tax Free in Canada*
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.
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

Thong silhouette sits lower on the hip with 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

It absorbs about 2 regular tampons worth of liquid—great for regular flow days, light bladder leaks, and sweat.

No-Show Style

Made from our signature buttery soft fabric with a wide, comfortable waistband. Wear it on its own or under your favorite pajamas.

Easy to Wash

Machine washable just like regular underwear.

Zoom

Isabelle has 40” hips and wears a Knix size M | Sola
Isabelle has 40” hips and wears a Knix size M | Sola
Isabelle has 40” hips and wears a Knix size M | Sola
| General
| General
| General
| General

How to Choose?

Essential

Drop
Drop
Drop
Drop
Drop
  • • Days you don’t need leak protection. Everyday freshness and moisture wicking.
  • tsp
    0 tsp

Heavy

Drop
Drop
Drop
Drop
Drop
  • • 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

Drop
Drop
Drop
Drop
Drop
  • • 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

Drop
Drop
Drop
Drop
Drop
  • • 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

Drop
Drop
Drop
Drop
Drop
  • • 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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4.0
Rated 4.0 out of 5 stars
Based on 239 reviews
Total 5 star reviews: 151 Total 4 star reviews: 20 Total 3 star reviews: 20 Total 2 star reviews: 14 Total 1 star reviews: 34
74%would recommend these products
ComfortRated 3.9 on a scale of 1 to 5
EffectivenessRated 4.1 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)
239 reviews
  • Rated 5 out of 5 stars
    4 minutes ago
    Comfortable

    I was told to size down because they stretch out a bit, so I got the small instead of medium. Comfortable and no leakage when wearing them without any other period product as back up

    Jenn P.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 days ago
    Wife approved

    I began to research underwear for built in absorption for the wife. After two kids, she has issues with leakage in certain situations and to counter this, she uses panty liners. These liners are not bad but not the best to use. I figured built in liners would likely be more sanitary and comfortable so I purchased her these thongs for Christmas. I like the colors and simply selected the correct size. The price was also a positive.

    She has truly enjoyed them so I purchased a thicker absorption pad panty. We will see how much she enjoys those.

    She likes the fit of the no show and feel of the stretchy fabric. She does warn on making sure to get the appropriate size because she thinks they will be constrictive if you get a size too small. She enjoys wearing them and I enjoy seeing her in them.

    Wife and husband approved.

    Jimmy R.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 days ago
    Perfect

    I have yet to be disappointed by anything that I’ve ordered from knix

    Lisa B.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 days ago
    Love these panties

    I got these to use with my flex disc because you can never be too careful and honestly I'm wearing them just about every day at this point. I started with 3 pair on BF sale, and at this point I own 7.

    They are great for a sneeze leak and spotting at the start and end of my period.

    They are also comfy enough I don't notice I'm wearing anything different than "regular" panties.

    The only time I will not wear these is to a cycle class. They chafe my pubic area and are very uncomfortable during a sweaty ride.

    Cecilia l.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 week ago
    Happy

    Great fit, comfortable! I usually find thongs uncomfortable but these are great!

    Sonya M.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    The best!

    Très satisfaite de mon achat.

    Il serait bien que tous les dessous ait le niveau d’absorption imprimé à l’intérieur. Lorsqu’on en a plusieurs ça aiderait :)

    Ève T.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    2 weeks ago
    Love these

    Love these underwear so much, they are my everyday underwear now. They give me the confidence to wear whatever I want and not worry. They will stretch a little after a few wears just like other brands that make these bonded seam (invisible) underwear. So if between sizes definitely size down and break in for a couple wears.

    Amanda
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    3 weeks ago
    Amazing!

    I absolutely love everything about them !

    Cora Y.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    4 weeks ago
    Comfortable

    Nice to look at and nice to wear

    Michelle L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    5 Stars

    Fit well and are comfortable.

    Sandra
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Very good underwear

    Very good product

    caroline L.
    Verified Buyer
    Was this helpful?
  • Rated 5 out of 5 stars
    1 month ago
    Light Leakproof Thong

    I love how these protect, feel and boost my confidence!

    Andrea P.
    Verified Buyer
    Was this helpful?