Leakproof UltraThin No-Show Bikini
Mix & Match: Buy 3+ Save 10%, 6+ Save 20%
• Our newest leakproof innovation provides more absorbency without the bulk.
• Great for leak protection, the ultra-thin liner absorbs about the same as 2.5 super tampons or 1 regular pad’s worth.
• Our patented 360 LeakSeal™ technology locks in leaks at every edge.
• The carbon cotton gusset top layer wicks away moisture from your skin.
• These underwear feature our signature buttery soft fabric.
• No-show construction is designed to be invisible under clothes, including workout leggings.
• Machine washable just like regular underwear.
Get the protection you want from periods and light bladder leaks while feeling comfortable and worry-free.
🇺🇸 Free standard shipping over $100*.
Free expedited shipping over $150*. Duty-free. (after discounts, before shipping + taxes)
Within 30 days of delivery, you may exchange for another size, style or store credit. We’re unable to provide refunds on underwear.
- Candace L.Verified Buyer1 hour agoRated 5 out of 5 starsWonderful
Love these for period week give me extra protection
ComfortRated 5.0 on a scale of 1 to 5Poor ExcellentEffectivenessRated 4.0 on a scale of 1 to 5Poor ExcellentSizingRated 0.0 on a scale of minus 2 to 2Runs Small True to Size Runs LargeWas this helpful? - KarenVerified BuyerYesterdayRated 5 out of 5 starsTry Knix! You’ll love this brand!❤️
I found Knix a couple years ago, replaced all my bras and undies… and then some😊… and haven’t yet stopped adding more pieces! I love this brand! I’m a 34 DDD and so decided to stick with sports bras for more support and wider straps. I will never wear underwire again! As for undies, bikini, French cut, boy short and even a couple full cut… fun, fun, fun! Colors, prints are all attractive! Fabric is lovely! I do wash as directed, cold water on delicate. I dry flat or gently hang to air dry. For reference, I’m 5’10”, 120lbs. I wear a large in bikini, medium in boy short, small/medium in French cut and full cut.
ComfortRated 5.0 on a scale of 1 to 5Poor ExcellentEffectivenessRated 5.0 on a scale of 1 to 5Poor ExcellentSizingRated 0.0 on a scale of minus 2 to 2Runs Small True to Size Runs LargeWas this helpful? - Mélissa G.Verified BuyerYesterdayRated 5 out of 5 starsMy daughter really enjoy your product. Thank you
Great product :)
EffectivenessRated 4.0 on a scale of 1 to 5Poor ExcellentComfortRated 4.0 on a scale of 1 to 5Poor ExcellentFitRated 1.0 on a scale of minus 2 to 2Runs Small True to Size Runs LargeEase of Use Rated 4.0 on a scale of 1 to 5Poor ExcellentEase of UseRated 4.0 on a scale of 1 to 5Poor ExcellentWas this helpful?
How to wash
Machine Washable: Wash with like colors, cold setting with mild detergent, do not bleach, iron, or dry clean.
Always refer to our Fabric & Care section for best drying practices.
Your leakproof questions, answered.
Our Leakproof technology features a built-in absorbent liner. Depending on the style you choose, the absorbency can range from about 1-17 tsp of liquid. The result? Confident protection from sweat, discharge, periods, and light bladder leaks.
A gusset is essentially a liner. It’s where you’ll find our leakproof technology. It’s built into the crotch section of the underwear.
Coverage at Knix comes in all shapes and sizes. If we’re talking about silhouettes, we go all the way from thongs to boxers.
We also offer high rise styles, like the Leakproof UltraThin No-Show High Rise, that sits just above the natural waist and gives full coverage through the stomach, hip & bum.
For extra liner coverage, look for undies that have an “extra-long liner” (usually 10”-14”), like in our Dream Short. And our Ultra Zones+ also have full bum coverage, too.
Have a suggested style or coverage? Just let us know. We love the feedback!
Many people refer to them as period underwear or period panties. But leakproof underwear covers you for all of life’s leaks, including periods (even your heaviest flows), sweat, light bladder leaks, postpartum, and discharge.