Join Our Rewards Program
Earn rewards and exclusive member-only benefits for free.
SuperPlus Leakproof® No-Show Boybrief
SuperPlus Leakproof® No-Show Boybrief
$39.00
CAD
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
39 Points
You May Also Like
Product Description
Comfort-First Fit
Ultimate Leakproof Protection
Day & Night Comfort
Machine Washable
Zoom
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
Our Best-Selling Underwear
Shop All
Restocked
Super Leakproof® Mini Dream Boxer
$48.00
CAD
Buy More, Save More
Color: Blue Stripe Polka Dot Limited Edition
+2
Restocked
Super Leakproof® Dream Boxer™
$48.00
CAD
Buy More, Save More
Color: Blue Stripe Polka Dot Limited Edition
+3
Leakproof UltraThin No-Show High Rise
$32.00
CAD
Buy More, Save More
Color: Cheetah Print Limited Edition
+4
Leakproof UltraThin No-Show French Cut
$27.00
CAD
Buy More, Save More
Color: Cheetah Print Limited Edition
+3
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
Recently Viewed
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.
Reviews Summary
Generated by AI from 72 most recent customer reviews
Last updated 1 month ago
Customers say these underwear are soft, comfortable, and provide reliable protection. Many praise the extended front-to-back coverage for overnight use and heavy flow situations. Common feedback highlights the secure fit and no-show design under clothing. However, some report sizing runs tight and note the padding creates visible lines under fitted garments. A few mention the waistband digs in or the back feels baggy. Overall, most customers appreciate the comfort and protection, though fit preferences vary by individual body type.
77%would recommend this product
Search
Keywords
Rating
Height
How do you use your Leakproof?
Usual Pant Size
97 reviews
- Rated 5 out of 5 stars19 hours agoSuperPlus Leakproof® No-Show Boybrief
SuperPlus Leakproof® No-Show Boybrief
HSHelen S.Verified Buyer - 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 Buyer - Rated 5 out of 5 stars5 days agoGood fit!
Confortable et sans tracas pour les mouvements.
TNtougas N.Verified Buyer - 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 Buyer - Rated 5 out of 5 stars1 week agoGreat
Love knix
DDdesiree d.Verified Buyer - Rated 5 out of 5 stars1 week agoLove
I love these briefs they are exactly what they say they are.
SMSheila M.Verified Buyer - Rated 5 out of 5 stars1 week agoLove the coverage
They absorb wonderfully
LFLori F.Verified Buyer - 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 Buyer - Rated 5 out of 5 stars4 weeks agoPerfect
Absolute comfort with no worries about leaks, yes please!
CBCynthia B.Verified Buyer - Rated 5 out of 5 stars1 month agoSuper plus Leakproof No-Show Boybrieg
Excellent product.
JDJoyce D.Verified Buyer - Rated 5 out of 5 stars1 month agoFeels good
The underwear you sent me feels good. I have purchased 10more Hope they get here soon.
LMLinda M.Verified Buyer - Rated 5 out of 5 stars1 month ago5 Stars
Love these for a cross dresser as it keeps everything flat and absorbs any leaks
MMikhal
