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FreeFlex™ Demi Bra
FreeFlex™ Demi Bra
$78.00
CAD
2 for $99
Our first underwire bra
Comfortable, flexible wire
Lifts and separates
Lightly lined molded cups
Size and Fit Guide
Use Our Calculator to Find Your Traditional Bra Size
Step 12 of 2
Your Results
Measure Your Under Bust
Measure Your Full Bust
Wearing an unpadded bra, wrap a measuring tape around the top of your ribcage. You’re looking for a snug fit - so we recommend tightening on the exhale and noting the smallest measurement to the decimal.
Wrap the measuring tape around the fullest part of your chest, making sure the measuring tape is paralell to the floor. Relax your shoulders and measure where it falls.
At Knix, your size is
Still have questions? Ask our virtual assistant about finding the perfect fit.
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Product Description
The Underwire Bra Reinvented
Wear tested for over 625 hours, providing unparalleled lift, separation, and support.
All Day Comfort
It's everything you want from an underwire bra without the downfalls of one.
Feels Made For You
Lightly lined, molded demi cups lift and separate for a great shape that looks amazing under lower necklines and T-shirts. Adjustable straps create the perfect fit.
Smooth Coverage
The ultimate t-shirt bra that appears invisible under clothes.
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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
How it Compares
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Molded cups for lift & support
Mesh detailing at bust to prevent spillage
Back mesh panels for a smooth silhouette
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Molded cups lightly lift & separate
Extra side coverage prevents spillage
Comfortable, wireless support
Revolution V-Neck Bra
Wireless, removable cups
Buttery-soft BeyondSmooth™️ fabric
Four-way stretch for total comfort
Uplift Push Up Bra
Embedded raised foam panel for natural lift
Molded cups define your shape
Comfortable, wireless support
FreeFlex™ Demi Bra
Comfortable, flexible underwire
Lightly lined cups
Lifts and separates
Revolution Shadow Mesh Bra
Wireless, removable cups
Buttery-soft BeyondSmooth™️ fabric
Mesh detail at bust prevents spillage
Revolution Scoop Bra
Wireless, rounded cups
Buttery-soft BeyondSmooth™️ fabric
Versatile scoop neckline
FREEFLEX™ TECHNOLOGY
Carbonized Flexible Wire
Rigorous Comfort Testing Wear
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Recently Viewed
Total 5 star reviews: 249 Total 4 star reviews: 76 Total 3 star reviews: 57 Total 2 star reviews: 54 Total 1 star reviews: 55
Reviews Summary
Generated by AI from 100 most recent customer reviews
Last updated 1 week ago
Customers say this underwire bra is comfortable and supportive, with many finding it surprisingly wearable all day. The flexible wire provides good shape and lift while feeling softer than traditional underwires. However, many reviews mention a persistent squeaking or creaking noise from the wire during movement. Sizing appears inconsistent, with several customers noting cups run larger than expected and bands fitting smaller. Some experience discomfort from the center wire sticking out or digging into the ribcage. While praised for comfort and support, the noise issue and sizing challenges affect overall satisfaction.
68%would recommend these products
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Usage - Bras
491 reviews
- Rated 5 out of 5 stars4 minutes ago5 Stars
The fit and comfort
IndigoReviewingFreeFlex Demi Bra - Last Call - Rated 5 out of 5 stars3 days agoGreat Bra!!
Perfect fit. Very comfortable with good lift. My new go to Bra❤️
Kathy N.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 week agoAwesome bra
I’ve been searching and trying so many different bras, came across this one and it’s a keeper! I absolute love how it fits? Doesn’t gape or cause overflow! 10/10
Sandy G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars2 weeks agoBra purchased
Love the bra. I will buy a couple more when I come to town. The service was beyond excellent.
Karen
Karen G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars2 weeks agoGreat bra
Comfie despite the wire support.
SARAH C.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars3 weeks agoMy favourite bra
My favourite bra! Its so soft and the wire is the perfect support. The quality is amazing. I love knix bras but this one takes the crown!!
Jessica C.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoGreat bra
I wasn’t sure about this bra because I usually enjoy something a little cuter looking. But I have to say I reach for this bra anytime I need something smoothing with great support. Will definitely buy another!
Henrietta B.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoFree flex Demi Bra
Very comfortable and great support. Would definitely buy again
Melissa E.Verified BuyerReviewingFreeFlex Demi Bra - Last Call - Rated 5 out of 5 stars1 month agoMy new fav bra!
Literally bought 3 of the Demi Flex bras in and considering buying a fourth in a new colour! Shipping is in a decent time frame!
Lydia J.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoGood
Unfortunately, I took small size, next time will be careful, but it is really good
Viktoriia Z.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoFinally!!
An underwire that’s comfortable! And supports. Loving this bra.
Amanda K.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month ago5 Stars
Very comfortable
normaReviewingFreeFlex Demi Bra - Last Call
