Teen Leakproof UltraThin No-Show Bikini
Bundle & Save: 3 for $65



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.
Hanging out or running to your next class? These period undies provide the ultimate comfort you want, plus ultra-thin protection you need from sweat, discharge and leaks. It’s a classic silhouette made with a super soft-and-stretchy, quick-drying material. It absorbs about the equivalent of 2.5 super tampons for an extra dose of confidence on those medium-flow days.
Key Features:
- 360LeakSeal™ patented technology designed to seal in leaks from every angle
- Soft and stretchy for comfort throughout the day
- Seamless look for any OOTD
- Quick dry for that fresh feel
🇨🇦 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.
Kt by Knix for Teens Underwear FAQs
Kt by Knix is designed for smaller and growing bodies to fit teens. Kt Period Underwear are available in teen sizes with smaller leg openings.
Super Absorbency
Absorbs 9–12 tsp (45–60 ml) of blood—that’s about 9–12 regular tampons or pads! Perfect for overnight protection or your teens heaviest days when changing into a fresh pair might not be convenient.
High Absorbency
Absorbs 4–8 tsp (20–40 ml) of blood, or the equivalent of 4–8 tampons or pads. These are perfect for heavy flow days.
Medium Absorbency
Absorbs up to 3 tsp (15 ml), or about 3 tampons or pads worth of blood. Ideal for light to medium flow days or as backup to tampons or period cups.
All of our period underwear, swimwear, reusable pads, and activewear have our patented leakproof technology built right in.
First Layer: Wicks away sweat and moisture while neutralizing odors to keep your teen fresh all day long.
Second Layer: A super thin, highly absorbent liner that holds the power of 3–20 tampons or pads.
Third Layer: A secure, liquid-resistant outer layer keeps leaks from happening.
The short answer: nope! Depending on the absorbency level of the period underwear and the heaviness of your teens flow, your teen can wear our period undies on their own or as a backup to tampons or menstrual cups. They can wear our High and Super absorbency underwear alone and be totally protected, while our Medium absorbency underwear can be worn alone on lighter days or as backup on heavier days.
- Melissa M.Verified BuyerHeight 5’6 – 5’8”Pant Size Purchased MUsage Period Back-Up2 days agoHeight 5’6 – 5’8”Pant Size Purchased MUsage Period Back-UpRated 5 out of 5 starsSecond time ordering!
I've ordered the seamless underwear for my daughter two times! She is 16 and loves the security of the period underwear and the style of the seamless fit. Would highly recommend.
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? - Jose M.Verified BuyerPant Size 2Size Purchased SUsage Primary Period Protection5 days agoPant Size 2Size Purchased SUsage Primary Period ProtectionRated 5 out of 5 starsCustomer service!
My order got delayed/ lost. Customer rep I talked to was very understanding. Researched to see the hold up and followed up to make sure my item was received.
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? - Dollface4681 S.Verified BuyerHeight <5’5”Usual Pant Size - Knixteen Womens 4-8Size Purchased - Knixteen Underwear M1 week agoHeight <5’5”Usual Pant Size - Knixteen Womens 4-8Size Purchased - Knixteen Underwear MRated 5 out of 5 starsPeace of mind
My daughter has been exclusively wearing Knix Teen underwear for over a year now and she refuses to wear anything else. Comfortable and give her (and I) peace of mind.
ComfortRated 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 LargeEffectivenessRated 4.0 on a scale of 1 to 5Poor ExcellentEase of UseRated 5.0 on a scale of 1 to 5Poor ExcellentWas this helpful?