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SuperPlus Leakproof® No-Show Bikini
New Colors
SuperPlus Leakproof® No-Show Bikini
$36.00
USD
Save 15% on 3+ | 20% on 5+ | 25% on 7+
Absorbs 7-11 super tampons
Front-to-back liner
Bonded seams prevent leaks
Machine washable
Size and Fit Guide
How to Measure
In order to select the correct sizing, we recommend you take the following measurements using a soft tape measure. If necessary, ask someone else to help.
Waist
Measure around the narrowest part of your torso, usually just above your belly button. Keep the tape snug and level, but not tight. The number where it meets is your waist measurement.
Hip
Stand with your feet together and measure around the fullest part of your hips and buttocks. Keep the tape level and snug, but not tight. The number where it meets is your hip measurement.
Build Your 3-Pack
SuperPlus Leakproof® No-Show Bikini
SuperPlus Leakproof® No-Show Bikini
SuperPlus Leakproof® No-Show Bikini
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Product Description
Comfort-First Fit
Ultimate Leakproof Protection
Day & Night Comfort
Machine Washable
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How to Choose?
Essential
- • Days you don’t need leak protection. Everyday freshness and moisture wicking.
-
0 tsp
Heavy
- • Extra peace of mind. For the first days of your cycle, light bladder leaks, or a full night's sleep without a leak.
-
about 8-14 tsp
-
about 1.5-3 regular pads
-
about 4-7 super tampons
-
about 1.5-3 menstrual cups
Light
- • Daily freshness. For sweat, discharge, period spotting, or backup protection.
-
about 1-3 tsp
-
about 1-3 pantyliners
-
about 1-3 regular tampons
-
about 0.5 menstrual cups
Moderate
- • For mid-cycle flow, surprise cough or sneeze leaks, or a really sweaty spin class.
-
about 4-8 tsp
-
about 1-1.5 regular pads
-
about 2-4 super tampons
-
about 0.5-3 menstrual cups
Ultra
- • Ultimate peace of mind. For the heaviest period days, light bladder leaks, unexpected postpartum flow, or overnight protection.
-
about 15-20 tsp
-
about 1.5-2.5 super pads
-
about 7-11 super tampons
-
about 2-3 menstrual cups
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PATENTED LEAKPROOF TECHNOLOGY
Our longest, most absorbent liner—ever.
Our original Fresh Fix Technology® features a built-in absorbent liner that soaks up about 7–11 super tampons’ worth of liquid—so you stay fresh, comfortable, and in control.
Soft Top Layer
Middle Layer
Leakproof Layer
Bottom Layer
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How to wash
Knix underwear is 100% reusable and machine washable, just like your regular undies.
Not required. But for best results, you can rinse your leakproof with cold water in the tub or sink before washing.
Machine wash on a cold, gentle cycle with mild detergent.
For their longest life, air drying is best. Hang or lay flat to dry.
Fabric softeners, bleach, ironing, or heat from the dryer.
What our customers are saying
Generated by AI from 55 most recent customer reviews
Last updated 4 months ago
Customers say these underwear are comfortable and provide good coverage, with many praising the extended absorbent area that goes from front to back. Users appreciate the confidence they provide during periods and for minor bladder issues. Many reviews mention the soft, silky fabric and that they don't feel bulky under clothing. However, some customers note sizing issues, with several saying they run small and recommend sizing up. Common concerns include occasional side leaks, bunching or riding up during movement, and that they may not be suitable for very heavy flows. Some users find the back portion thick and less breathable. Despite mixed experiences with leak protection, most customers express satisfaction and plan to purchase again.
83%would recommend this product
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How do you use your Leakproof?
Usual Pant Size
89 reviews
- Rated 5 out of 5 stars24 seconds agoFit wonderfully,great leak proof design
These are very comfortable and fit great plus they are super leak proof. so far not a single leak in them.I am very happy with these undies.
SGStephanie G.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars6 hours ago5 Stars
the only underwear I wear. I'm older now & having had 5 children, my pelvic wall isn't the strongest. I'm menopausal & I love these underwear so much, I've bought them for my older sisters & they agree that they are the best.
AAlbertaReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars3 days agoBikini style
Didnt need the new super protection style? But they are smooth and comfortable in spite of the b additional coverage l
JMJoyce M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 4 out of 5 stars6 days agoI wish I had found these sooner
I love these underwear. The biggest benefit for me is that the lining goes all the way up. I wish there were more colour options with this feature.
My only complaint is that my first pairs are not holding up. I’m not sure if I was washing them incorrectly, but the stitching is coming undone on a couple pairs. Also, the lining is disintegrating on some pairs. I’m still giving a 4 star review because I still love them despite the issues, and because I’m not entirely sure I’m not to blame for not rinsing them sooner or washing them incorrectly.
JCJennifer C.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars1 week agoGreat post partum undies!
I am such a huge fan of these super plus leakproof underwear from Knox - they’ve given me such confidence in doing activities where incontinence might be a concern 16 months post partum. Cannot recommend them enough!
HMHilary M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 3 out of 5 stars2 weeks agoLeaked right through the middle
I wore it for the first time ever for bed and when I woke up in the morning, it leaked straight through the middle and went all over my pants. Maybe it’s better just to wear it during the day.
ELEva L.Verified ReviewerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 3 out of 5 stars2 weeks agoThey make me sweat!
I was excited to try this style because if I leak, it tends to be at night, towards the back so the extended liner sounded ideal, but omg these make me so sweaty! It could be 50 degrees in my house and my buns would still be sweating in these. Honestly, I just can’t wear them, I’ll stick to the ones with the normal sized gusset and wear a pad as a backup.
LGLeAnn G.Verified ReviewerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars2 weeks agoGreat!
Fit great and work well!
MKMelissa K.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars3 weeks ago5 Stars
Nice high quality
MMaleahReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars3 weeks agoWorks so well!
I bought these for my teen girls because they were often leaking on their sheets overnight. No leaks since! 🙌
KMKelly M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars3 weeks ago5 Stars
Really no shoe and comfortable.
AamiReviewingSuperPlus Leakproof® No-Show Bikini - Rated 5 out of 5 stars3 weeks ago5 Stars
Great underwear.
AamiReviewingSuperPlus Leakproof® No-Show Bikini
