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Leakproof UltraThin No-Show Bikini
#1 Daytime Solution
Leakproof UltraThin No-Show Bikini
$27.00
CAD
Buy 3+ Save 15%, Buy 5+ Save 20%
Absorbs about 2.5 super tampons
Invisible under clothes
Moderate protection without the bulk
Machine washable
Size and Fit Guide
How to Measure
In order to select the correct sizing, we recommend you take the following measurements using a soft tape measure. If necessary, ask someone else to help.
Waist
Measure around the narrowest part of your torso, usually just above your belly button. Keep the tape snug and level, but not tight. The number where it meets is your waist measurement.
Hip
Stand with your feet together and measure around the fullest part of your hips and buttocks. Keep the tape level and snug, but not tight. The number where it meets is your hip measurement.
Build Your 3-Pack
Leakproof UltraThin No-Show Bikini
Leakproof UltraThin No-Show Bikini
Leakproof UltraThin No-Show Bikini
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Product Description
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 your regular underwear.
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How to Choose?
Essential
- • Days you don’t need leak protection. Everyday freshness and moisture wicking.
-
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.
-
about 8-14 tsp
-
about 1.5-3 regular pads
-
about 4-7 super tampons
-
about 1.5-3 menstrual cups
Light
- • Daily freshness. For sweat, discharge, period spotting, or backup protection.
-
about 1-3 tsp
-
about 1-3 pantyliners
-
about 1-3 regular tampons
-
about 0.5 menstrual cups
Moderate
- • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
-
about 4-8 tsp
-
about 1-1.5 regular pads
-
about 2-4 super tampons
-
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.
-
about 15-20 tsp
-
about 1.5-2.5 super pads
-
about 7-11 super tampons
-
about 2-3 menstrual cups
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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
Middle Layer
Leakproof Layer
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How to wash
Knix underwear is 100% reusable and machine washable, just like your regular undies.
Not required. But for best results, you can rinse your leakproof with cold water in the tub or sink before washing.
Machine wash on a cold, gentle cycle with mild detergent.
For their longest life, air drying is best. Hang or lay flat to dry.
Fabric softeners, bleach, ironing, or heat from the dryer.
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 5 months ago
Customers say these period underwear are comfortable and provide effective protection without the bulk of traditional pads. Many appreciate the soft, buttery fabric that feels like regular underwear and the no-show design under clothing. Users frequently mention confidence during workouts, daily activities, and even swimming. Parents often purchase these for teenage daughters who love the comfort and security they provide. Common feedback includes praise for the absorbency and leak-proof performance. However, several reviews mention sizing inconsistencies, with some finding recent purchases run smaller than previous orders. A few customers note the leg holes can feel tight or that the fit varies between different fabric types.
84%would recommend these products
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807 reviews
- Rated 5 out of 5 stars2 weeks ago5 Stars
So happy to get this, and the box set look it comes in omg the ACOTAR collab is amazing and the product high quality
AAddisonReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set Thorns & Roses/Mist & Fury/Wings & Ruin/Frost & Starlight/Silver Flames / L - Rated 5 out of 5 stars4 minutes ago5 Stars
soooo cuteee
AAmyReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set Thorns & Roses/Mist & Fury/Wings & Ruin/Frost & Starlight/Silver Flames / M - Rated 5 out of 5 stars30 minutes agoLove the Leakproof Ultra Thin No-Show bikini
I bought 2 leakproof ultrathin no show bikinis for my daughter. She loves them. She said that they are very comfortable and as if you are not wearing anything.
I bought a beige colour and a rose print one which is very beautiful.
HGHilka G.Verified BuyerReviewingLeakproof UltraThin No-Show Bikini Spring Court Bloom / M - Rated 5 out of 5 starsYesterdayLove the colors!
These are the first Knix underwear I’ve purchased and I will definitely be buying more! The quality is high end! So comfortable and I love the colors!
AEAlexis E.Verified BuyerReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set Thorns & Roses/Mist & Fury/Wings & Ruin/Frost & Starlight/Silver Flames / M - Rated 5 out of 5 stars2 days agoso sexy
so sexy for leakproof
LLL. L.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack - Rated 5 out of 5 stars3 days agoComfy comfy
Very comfortable. I don't really need the period function. But I wanted the ACOTAR collections. Would purchase again if there was another collab. Rating middle ground for effectiveness because I can't tell you
ARAriana R.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack Ember Fox/Dark Cherry/Autumn Tapestry / L - Rated 5 out of 5 stars3 days ago5 Stars
Love it. Confortable and good price too.
HHilkaReviewingLeakproof UltraThin No-Show Bikini Warm Sand / M - Rated 5 out of 5 stars3 days ago5 Stars
Bought 2 pairs of leakproof UltraThin No-Show Bikini for my daughter. She loves them . She says that it’s very comfortable and it’s as if you are not wearing anything. 🙂. Love the rose pat- it’s very pretty.
HHilkaReviewingLeakproof UltraThin No-Show Bikini Spring Court Bloom / M - Rated 5 out of 5 stars3 days ago5 Stars
je les adores
MMarieReviewingLeakproof UltraThin No-Show Bikini Black / L - Rated 5 out of 5 stars4 days agoGreat
Comfy and effective - so far so good.
KKKara K.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack Ink That Binds/Midnight/Velaris Night Sky / L - Rated 5 out of 5 stars4 days agoGreat product
This brand it’s amazing, the products are very comfortable, easy to wear, very effective and soft.
NLNora L.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack Ink That Binds/Midnight/Velaris Night Sky / S - Rated 5 out of 5 stars4 days agoLove!
So cute! I love them
MCMeghan C.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack Ink That Binds/Midnight/Velaris Night Sky / M
