Leakproof Cotton Boybrief
Bundle & Save: 3 for $75





Leakproof Cotton Boybrief
Bundle & Save: 3 for $75
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.
• Great for daytime protection, the ultra-thin liner absorbs about the same as 3 super tampons or 1.5 regular pads worth of liquid.
• The innovative floating gusset provides leak protection from every angle.
• The cotton-spandex blend feels luxurious against your skin.
• Certified according to OEKO-TEX® STANDARD 100, Product Class I : HK020 246396 TESTEX
• Machine washable just like regular underwear.
Get the protection you want from periods and light bladder leaks while feeling comfortable and worry-free.
• Brief shorts style
• Absorbs the same as about 3 super tampons’ worth of liquid
• Quick dry liner
• Soft, cotton-spandex blend
🇨🇦 Free standard shipping over $100.
(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.
Your leakproof questions, answered.
*Offer valid on select underwear styles on knix.com and knix.ca, while supplies last. When you purchase three or more eligible styles from the same category, you’ll receive the corresponding offer:
Light: 3 for $60
Heavy: 3 for $75
Overnight: 3 for $99
Exclusions: Sale items, Super Leakproof® Dream Boxer, Leakproof CoreLove High Rise, Leakproof Modal Rib Boxer Brief, Luxe Modal Leakproof Sleep Boxer, Leakproof Cotton Modal Bikini, Leakproof Cotton Modal High Rise, all Thigh Saver styles.
Discount is automatically applied at checkout and is based on eligible items in your order. No rain checks or price adjustments on previous purchases.
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.
- Stephanie4 days agoRated 5 out of 5 stars5 Stars
They are super comfortable, and they fit true to their size guide. Work super well. I'm glad i got them!
Was this helpful? - Sophie T.Verified BuyerHeight <5’5”Pant Size 14Pant Size Purchased LUsage Primary Period Protection1 week agoHeight <5’5”Pant Size 14Pant Size Purchased LUsage Primary Period ProtectionRated 5 out of 5 starsComfortable
These briefs are so comfortable. They don’t roll down or ride up. My favourite underwear!
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 ExcellentWas this helpful? - Kathy D.Verified BuyerHeight <5’5”Pant Size 14Pant Size Purchased MUsage Light Bladder Leaks1 week agoHeight <5’5”Pant Size 14Pant Size Purchased MUsage Light Bladder LeaksRated 5 out of 5 starsLady of th House
They fit so nice and feel just great on I even forgot that they are waterproof. Best underwear I have ever owned.
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 ExcellentWas this helpful?