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FreeFlex™ Demi Bra
FreeFlex™ Demi Bra
$68.00
USD
Buy 2 Bras Get 10% Off
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
What our customers are saying
Generated by AI from 100 most recent customer reviews
Last updated 5 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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515 reviews
- Rated 5 out of 5 stars52 minutes agoLove this bra!
It’s so hard to find a great fit in the world of bras! This one is fantastic. I love the fabric, the fact that the back stays in place, the lift and separation and, really, everything about it. I highly recommend!
KGKathleen G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 1 out of 5 stars2 days agoExtremely uncomfortable
I have two of these bras and both of them are unbelievably uncomfortable. The underwire in both bras dig into my ribs worse than any other bra I’ve ever worn, because for some reason the underwire’s are very misshapen and don’t curve with the body at all.
OPOlivia P.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 4 out of 5 stars1 week agoDemi bra
comfortable, easy to wear all day
JRJudy R.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 week agoBest Bra Ever!!!
I’ve tested and tried many brands and types of bra but always ended up being unsatisfied until I tried the demi bra and bought 3 pairs at once. Since I bought them, I refuse to go back to any other bras. I recommend it to my friend and she says it’s the best bra she ever had. It’s worth every penny! Worth the comfort and feel. Thank you for making a bra that doesn’t make wearing bra a nightmare anymore!
MTMamata T.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars2 weeks agoSo great!
Perfect fit!
BMBethany M.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 4 out of 5 stars3 weeks agoComfy and stylish
Looks and feels great under a Tshirt. Great option without discomforts felt with other bras.
LPLaurie P.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars3 weeks agoDemi Bra
Really like it , shape feel of material.
ENElizabeth N.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars3 weeks ago100%!
Très confortable, la taille était bonne et le tissu est vraiment de bonne qualité. C’est cher mais ça vaut la peine. Je vais en commander d’autres pour pouvoir porter ce modèle tous les jours. 👌🏻
CMCamélie M.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars4 weeks agoUnderwire bra
I got the underwire it’s a great bra it just makes a crinkle sound when I move from the underwire I really like it very comfortable
AGAngela G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoFound my forever bra, now more colours please :)
I love this bra. The flexible wire feels like a game hanger, as there is nothing worse than when an underwire snaps midday. This bra is VERY comfortable and flexible enough to conform to the body. I also love the smooth appearance under clothing, both on the chest and on the back.
MHMaegan H.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoBra leopard
The fit is perfect recommend for anyone
SGSharon G.Verified BuyerReviewingFreeFlex™ Demi Bra - Rated 5 out of 5 stars1 month agoFirst time with FreeFlex
This is my first time wearing this particular kind of Knix bra. It feels as wonderfully comfortable as the others I have worn!
CWConnie W.Verified BuyerReviewingFreeFlex™ Demi Bra
