Luxe Modal Leakproof Sleep Boxer
Mix & Match: Buy 4+ Save 15%, 7+ Save 25%





Luxe Modal Leakproof Sleep Boxer
Mix & Match: Buy 4+ Save 15%, 7+ Save 25%
Knix period underwear and pads are now sales tax-free in Canada.* We celebrate improvements to the accessibility and affordability of essential period care products.
Designed with a cloud-soft modal fabric blend and shadow-sheer waistband detailing, this Leakproof Sleep Boxer lets you rest easy without worry of leaks.
🇨🇦 Free standard shipping over $100.
Free expedited shipping over $150.
(after discounts, before shipping + taxes) All items ship from within Canada.
Within 30 days of delivery, you may exchange for another size, style or store credit. We’re unable to provide refunds on underwear.


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.
*Period underwear and pads are exempt from federal sales tax in Canada. They are also exempt from most provincial / harmonized sales taxes. But are subject to the following provincial sales tax rates which will apply to orders shipped to the following provinces and to orders purchased in retail stores located in the following provinces: British Columbia and Manitoba: 7% PST; Saskatchewan: 6% PST.
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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!
- Stephanie D.Verified Buyer4 minutes agoRated 5 out of 5 starsThey work!
These are very comfortable and no leaks!
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? - TeresaVerified Buyer4 weeks agoRated 5 out of 5 starsModal fabric is the best!
I'm absolutely in love with these. I wear them day and night for my LBL. The modal fabric is by far the best for me as I don't find them hot. They are super soft and fit like a glove. (I was on the borderline for sizing so I sized down and they fit perfectly.) The protection is perfect for my LBL and they don't feel bulky. They feel like regular underwear in terms of gusset comfort. I only wish they were a couple inches shorter so I can wear them under my bermuda shorts in the summer. I'll continue to buy modal fabric. I now have 8 pairs! (I also love the cotton modal high rise underwear. I hope they bring them back as they are currently out of stock.)
ComfortRated 5.0 on a scale of 1 to 5Poor ExcellentEffectivenessRated 5.0 on a scale of 1 to 5Poor ExcellentFitRated 0.0 on a scale of minus 2 to 2Runs Small True to Size Runs LargeEase of UseRated 5.0 on a scale of 1 to 5Poor ExcellentEase of Use Rated 5.0 on a scale of 1 to 5Poor ExcellentWas this helpful? - H1 month agoRated 5 out of 5 starsSo comfortable
I wasn’t sure about the insert and how it looked but you really can’t see it and dang, these are comfortable. Make them non-leakproof for the rest of the month and in a 3 pack please! I’d wear them every night!
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?