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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
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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 53 most recent customer reviews
Last updated 3 months 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.
77%would recommend this product
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101 reviews
- Rated 1 out of 5 stars1 hour agoThe SuperPlus Leakproof No Show Boybrief. Leak
They leak so I won't be purchasing more.
MAMarisa A. M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars19 hours agoSuperPlus Leakproof® No-Show Boybrief
SuperPlus Leakproof® No-Show Boybrief
HSHelen S.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 starsYesterdayComfort meets protection
I was skeptical to purchase due to having large muscular thighs but the material is surprisingly comfortable and I’m now obsessed. As someone who has sensory issues, these underwear are exceptional!
SSSammantha S.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars5 days agoGood fit!
Confortable et sans tracas pour les mouvements.
TNtougas N.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoExcellent!
I love the style, and very absorbent for nighttime use. They are the only ones I use!
MLMichelle L.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoGreat
Love knix
DDdesiree d.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoLove
I love these briefs they are exactly what they say they are.
SMSheila M.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week agoLove the coverage
They absorb wonderfully
LFLori F.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars1 week ago5 Stars
Was delivered as expected.
CCharleneReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars3 weeks agoBest thing I own
Just buy them. I've been a pad user the majority of my life and these absolutely changed my periods for the better. I used them during the day AND overnight, no leaks. Super comfortable.
BWBryanna W.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 4 out of 5 stars3 weeks ago4 Stars
If you have heavy periods, these will never replace all of your period products. But theyre nice to have. I cant give it 5 stars because I think the gusset is needlessly narrow. It could be wider and provide better protection/absorption that way. Not to overshare but i was wearing a tampon and still leaked out the side of my underwear on a heavy day because of the narrow gusset. I do like these better than the other pairs I have because the absorbent part goes all the way up in front and back, but more protection width-wise would be great
KKristenReviewingSuperPlus Leakproof® No-Show Boybrief - Rated 5 out of 5 stars4 weeks agoPerfect
Absolute comfort with no worries about leaks, yes please!
CBCynthia B.Verified BuyerReviewingSuperPlus Leakproof® No-Show Boybrief
