Teen Leakproof UltraThin No-Show Bikini
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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.
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.
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.
- Sandra C.Verified BuyerI'm a... Parental FigureI purchased for... A Teenager/TweenPant Size Teen 00-2Size Purchased XSUsage Primary Protection1 hour agoI'm a... Parental FigureI purchased for... A Teenager/TweenPant Size Teen 00-2Size Purchased XSUsage Primary ProtectionRated 5 out of 5 starsRevolutionary Feminine Protection
KT by Knix period underwear has been an absolute game-changer for my teen! As a dancer, she needs to feel confident and comfortable while performing, and traditional pads and liners just weren’t cutting it—they were bulky, uncomfortable, and constantly shifting. I started looking for alternatives and came across KT by Knix. After ordering a couple of pairs to try, she was immediately sold!
These are true to size, super comfortable, incredibly absorbent, and most importantly—completely leakproof. Whether she’s at practice, in class, or on stage, she can focus on dancing without worrying about leaks or discomfort. The confidence and peace of mind these provide are priceless! I highly recommend them to any parent looking for a reliable and comfortable period solution for their active teen.
QualityRated 5.0 on a scale of 1 to 5Poor ExcellentComfortRated 5.0 on a scale of 1 to 5Poor ExcellentSizingRated 0.0 on a scale of minus 2 to 2Fits Small True to Size Fits LargeEffectivenessRated 5.0 on a scale of 1 to 5Poor ExcellentWas this helpful? - Jennifer H.Verified BuyerPant Size Teen 00-2Size Purchased SUsage Primary Protection, Period19 hours agoPant Size Teen 00-2Size Purchased SUsage Primary Protection, PeriodRated 5 out of 5 starsPerfect
Works perfectly for my daughter. She loves the feel of the fabric and the prints. She’s normally quite sensitive to fabrics and seams, but has no problem with these.
QualityRated 5.0 on a scale of 1 to 5Poor ExcellentComfortRated 5.0 on a scale of 1 to 5Poor ExcellentSizingRated 0.0 on a scale of minus 2 to 2Fits Small True to Size Fits LargeEffectivenessRated 5.0 on a scale of 1 to 5Poor ExcellentWas this helpful? - Rachel M.Verified BuyerPant Size Teen 4-10Size Purchased MUsage Period2 weeks agoPant Size Teen 4-10Size Purchased MUsage PeriodRated 5 out of 5 starsAmazing and thin!
These are amazing. So comfortable and thin. And they don't leak!
QualityRated 5.0 on a scale of 1 to 5Poor ExcellentComfortRated 5.0 on a scale of 1 to 5Poor ExcellentSizingRated 0.0 on a scale of minus 2 to 2Fits Small True to Size Fits LargeEffectivenessRated 5.0 on a scale of 1 to 5Poor ExcellentWas this helpful?