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SuperPlus Leakproof® No-Show Boybrief
SuperPlus Leakproof® No-Show Boybrief
$39.00
USD
Buy 3+ Save 15%, Buy 5+ Save 20%
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 Boybrief
SuperPlus Leakproof® No-Show Boybrief
SuperPlus Leakproof® No-Show Boybrief
Rewards Members Earn
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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.
Total 5 star reviews: 48 Total 4 star reviews: 9 Total 3 star reviews: 7 Total 2 star reviews: 5 Total 1 star reviews: 7
What our customers are saying
Generated by AI from 53 most recent customer reviews
Last updated 1 week ago
Customers say these boybrief underwear provide excellent overnight protection with front-to-back coverage that prevents leaks. Many appreciate the soft, comfortable fabric and full coverage design. Users find them particularly effective for heavy flow days and overnight use, with some noting they can wear them for 12+ hours without issues. Several mention the sizing runs large and recommend sizing down for a better fit. While most praise the comfort and protection, some find the waistband too tight or the leg openings too loose. A few users note the absorbent pad feels thick or bulky compared to other styles. The extended coverage from front to back is frequently highlighted as a key benefit for preventing nighttime leakage.
75%would recommend this product
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Rating
76 reviews
- Rated 3 out of 5 stars21 seconds agoSaggy Butt
I was looking for more coverage than my beloved Super Leakproof Boy Shorts, hoping these SuperPlus Boy Briefs would fit as well but provide more confidence. I ordered my usual size L, but these Boy Briefs are loose and saggy. I admit to having a pretty flat bum, but I this style failed my expectations. Normally I love my Knix!
Jenifer C.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars22 hours agoComfy and never leaks!
This is my first time trying Knix and after a few months of wearing them I’m obsessed!! They don’t leak while I sleep at night even though I toss and turn a lot. And the fabric is super stretchy so even if I’m bloating and crampy im still comfortable. Will definitely be buying again.
Emerald M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 2 out of 5 stars3 days agoToo tight and not very absorbant...
These new knix are Too tight (both small and medium were too tight and I am normally a small in everything; I only weigh 110 pounds and I am in shape) and they are not very absorbant. These new knix are not an improvement over the older ones.
JENNIFER M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 2 out of 5 stars3 days agoLeaked though the side within a few hours.
Leaked through the side within a few hours. Didn't feel secure enough to sleep in them. Kind of feels baggy like a diaper in the back. Not happy with them for the price and wish I could return them 😕
Briahna M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars4 days agoLove my new underwear
Very much comfortable and soft !
Amelie A.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 1 out of 5 stars6 days agoNot so leakproof…
I have to admit I’m extremely disappointed in this product… I have fairly heavy periods in the first day or two of my cycle, and my biggest problem with pads is that they never go up high enough or wide enough at the back. I’d hoped this product would finally give my poor pyjamas some safety…. Well, the maximum coverage was effective at the front and back, but the actual center of the pad, where you’d expect it to be able to handle the flow? I put on a fresh pair before bed and it didn’t even last 8 hours. By morning I had leaked out the sides of the center, where the fabric is thinner, and onto my bottoms. For what is supposed to be the maximum absorbency, it sure doesn’t absorb very well!
I don’t normally go out of my way to write bad reviews, but for all the aggressive advertising I saw for this brand being supposedly “leakproof”, I’m extremely disappointed that it couldn’t even perform at least as well as a heavy overnight pad. Guess now I have some expensive underwear to sit at the back of my drawer. :(
EmiVerified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoSo comfy!
Best pair I’ve gotten from knix. Fits well, love the extended lining, and is so comfy
Stephanie S.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoSuper plus boybrief
Love them gives more coverage that I need!!!!
Shay M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoBest period panty for heavy flow
These panties have changed the 2 days during my period that I bleed out of my tampon every month. They give me so much security at work knowing I won’t have to go home and change clothes. Love these so much that I bought some for my daughter. They have helped us so much!
Kristin D.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoExcellent boybrief
I wore for the first time at night and experienced no leaks or soggy feeling. It was comfortable and perfectly held up on my heavy days.
Tricia L.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 4 out of 5 stars1 week agoLoved these!
So glad I bought these. Very comfortable, sizing was great. No leaks
Amanda C.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 2 out of 5 stars1 month agoVery disappointed
Unfortunately these panties are not worth the money I spent. The lining stays wet, a strong odor is present at the end of the day. I have 6 pair and would not order again. A regular pair of underwear at 1/3 or less of the cost combined with an Always discreet pad, level 4 is far superior to your product.
SUZAN M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief
