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Leakproof UltraThin™ No-Show Bikini 3-Pack
Bundle Deal
Leakproof UltraThin™ No-Show Bikini 3-Pack
$68.00
USD
$81.00
Save $13
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.
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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
Recently Viewed
What our customers are saying
Generated by AI from 100 most recent customer reviews
Last updated 5 months ago
Customers say these period underwear are comfortable and provide excellent protection without the bulkiness of traditional pads. Many appreciate the thin, no-show design that works well under clothing and the stylish patterns like polka dots. Users frequently mention the confidence and peace of mind these provide during periods, workouts, and daily activities. Several note they're particularly good for teens and lighter flow days. However, common concerns include sizing inconsistencies, with many finding recent purchases run smaller than expected. Some mention the front coverage could be longer, and a few experience issues with leg holes being too tight. Despite sizing challenges, most customers praise the comfort, absorbency, and quality of the product.
86%would recommend these products
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How do you use your Leakproof?
Usual Pant Size
808 reviews
- Rated 5 out of 5 stars4 minutes agoBeautiful prints!
I love the prints in this 3 pack! The underwear fits well with just the right amount of stretch. I feel dry (using for light bleeding days so far) and notice no odor.
SPSarah P.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack - Rated 5 out of 5 stars9 minutes agoMarketing Genius!
I had been wanting to try the knix period underwear so this was the perfect excuse but the packaging takes this over the top. Kudos to whomever came up with this idea! I love that the underwear matches the book colors and has the cover art on the hip. The underwear also fits well, just the right amount of stretch and keeps me feeling dry/no smell.
SPSarah P.Verified BuyerReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set - Rated 5 out of 5 stars11 hours agoLeakproof UltraThin No-Show Bikini
Great fit
ADAnastasia d. R.Verified BuyerReviewingLeakproof UltraThin No-Show Bikini - Rated 5 out of 5 stars12 hours agoHighly recommend
These are the perfect trifecta: Comfortable, cute,and functional
JWJennifer W.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack - Rated 5 out of 5 stars15 hours 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 - Rated 4 out of 5 stars16 hours agoLove ACOTAR
They are nice but they fit a little more snug than I would like. Love the designs though.
RBRaylina B.Verified BuyerReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set - Rated 4 out of 5 stars23 hours agoLeak Proof
So comfy and I do not even feel them on.
DRDeanna R.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack - Rated 3 out of 5 starsYesterdayJust okay
I loved the idea of these and the vibrant colors but I know the graphic will eventually peel off due to use and the sizes run slightly small. I wear a size medium or large normally, I choose size large bc who wants tight period underwear and I am glad it did because there is no way the medium would have been comfortable. Overall I am happy with my purchase because I needed more period underwear but not super impressed. Also the search on this website stinks once I ordered the set a found a cuter acotar set that I would have rather purchased.
KXKersten X.Verified BuyerReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set - Rated 5 out of 5 starsYesterday5 Stars
These give me peace of mind and help me feel comfortable. My only frustration is the amount of packaging because each piece was in a separate box inside of a larger box.
GGabrielleReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set - 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 - Rated 5 out of 5 stars2 days agoso sexy
so sexy for leakproof
LLL. L.Verified BuyerReviewingLeakproof UltraThin™ No-Show Bikini 3-Pack - Rated 4 out of 5 stars2 days agoBooktok came in amazing!
I love the ACOTAR cross! It was really tight compared to my other Knix products but they have kept up very well.
SCSadie C.Verified BuyerReviewingACOTAR™ Leakproof Ultrathin™ No-Show Bikini Box Set
