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FreeFlex™ Demi Bra
FreeFlex™ Demi Bra
$68.00
USD
2 for $90
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.
Still have questions? Reach out to info@knix.com to learn more about our sizing.
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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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Extra side coverage prevents spillage
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Revolution V-Neck Bra
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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: 253 Total 4 star reviews: 75 Total 3 star reviews: 58 Total 2 star reviews: 59 Total 1 star reviews: 54
What our customers are saying
Generated by AI from 100 most recent customer reviews
Last updated 2 months ago
Customers say this underwire bra offers excellent comfort and support for many users, with several praising it as the most comfortable underwire bra they've owned. Many reviews mention the soft fabric and good lift it provides. However, common feedback includes a significant squeaking or creaking noise from the underwire that occurs with movement, which many find annoying and noticeable to others. Frequent comments address sizing inconsistencies, with some finding it runs small while others experience gapping or poor fit. Several users note discomfort at the center gore area between cups, and some mention strap adjustment issues. While many customers became repeat purchasers and highly recommend it, others found the noise and fit problems made it unwearable despite the comfort.
67%would recommend this product
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499 reviews
- Rated 4 out of 5 stars3 minutes agoGreat fit and comfortable!
Great fit and comfortable. Makes squeeking sounds tho, lol
SRSherrie R.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 starsYesterdayBest bras ever
This bra is comfortable. Best support and you can’t feel the wire. It’s a great bra!
TMTiffany M.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars5 days agoFreeFlex Demi Bra
Most comfortable bra!
EBElizabeth B.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 week agoPerfect every day bra!
I was looking for an everyday wired bra since my old ones had been worn to the ground, and I'm glad I decided to give Knix's wired bras a try. I know wired bras aren't for everyone, but I personally like the extra security and support they provide. The FreeFlex Demi Bra definitely delivers for everyday wear. The underwire doesn't dig in, the band feels soft and silky, and nothing about it feels restrictive. It provides great lift and support while still being comfortable. The quality also stands out! It feels well made and durable. It's definitely a bit pricey, but the comfort, support, and quality make it worth it.
KKnix1 week agoHey Francine!
This is amazing! We're so happy our FreeFlex Demi Bra is giving you that perfect everyday comfort and support. Thanks for giving our wired bras a try!
Team Knix
FFrancineVerified BuyerReviewingFreeFlex™ Demi Bra - Rated 4 out of 5 stars2 weeks agoSummer Bra
This bra felt light and thin during summertime.
BTBetty T.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars2 weeks agoComfortable underwire
I haven’t been able to wear an underwire bra for years. So when I saw Knix came out with one I was curious. I went in store and tried it on and I ended up buying 2! I’ve had them for a month or so now and I haven’t had any issues with the underwire. They’re quite comfortable. I’m very happy with my purchase.
KKnix2 weeks agoHey Kaitlin!
This is amazing! We're so thrilled our FreeFlex™ Demi Bra brought comfortable underwire back into your life. Thanks for giving us a try!
Team Knix
KFKaitlin F.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars4 weeks agoFreeFlex Demi Bra
Super comfortable and very flattering. I love it!
KKnix4 weeks agoHey Mary!
Thanks so much for taking the time to review our FreeFlex™ Demi Bra! We're so happy to hear you're loving the comfort and flattering fit!
Team Knix
MGMary G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 3 out of 5 stars1 month agoNot as good as usual
I have recently lost some weight so decided to downsize a cup. I ordered one demi bra to see how it fit. Other than the fact it had underwire (my fault for not reading the description properly and assuming all knix were wireless) it was fine. So I decided to take advantage of the two for 99 special and ordered two more.
After wearing them I found that there was a large "bump" where the cup met the flat front piece they were attached to. Also one scratched at the back where the clasp was. I made adjustments to see if I could resolve this issue, made some improvements but they still do not fit at the cup.
I have worn them and adjusted them so I did not feel comfortable about returning them, but wanted to let you know about this issue.
JEJoan E.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month ago5 Stars
I was unsure about buying these because of the previous reviews, but I love this bra!! it feela really secure and super comfortable.
GGretchenReviewingFreeFlex™ Demi Bra - Rated 1 out of 5 stars1 month agosqueaky and poor fit
This bra didn't fit well. The wires were squeaky and it buckled in the centre creating a very odd look. Returning.
EHelaine h.Verified ReviewerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoFinally back to underwires!
I swore off underwires. The digging, the pinching, the discomfort. But let’s be honest, nothing lifts and separates like underwire. I took a chance and tried the Knix Demi and I’m obsessed. It’s comfortable and fits perfectly, like all of my other wireless Knix bras. But this one makes me feel so much more feminine. The only downfall is it’s a little “squeaky” but I’m hoping that fades with time. Please make some more fun colors in this bra! I will keep buying them!
KKnix1 month agoHey Beth!
We're so thrilled you're obsessed with the FreeFlex™ Demi! Love that you found the perfect balance of comfort and lift. More fun colors are definitely on our wishlist too!
Team Knix
BNBeth N.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoI will only ever buy this bra!
Beautiful quality and fit! So comfortable.
KKnix1 month agoHey Maxine!
This made our day! We're so thrilled you're loving the quality and comfort of our FreeFlex™ Demi Bra. There's nothing better than finding your perfect bra!
Team Knix
MBmaxine b.Verified BuyerReviewingFreeFlex™ Demi Bra
