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Power micromesh is surprisingly supportive [Aube 1]
Triangle cut is low coverage in the front and sides [Aube 1]
Adjustable hook and eye and strap sliders in the back[Aube 1]
Wide elastic bland is comfortable and supportive
Hannah is a 36DD in our size 4 [Hannah 4]
Black power micromesh is subtly sheer [Hannah 4]
The back of the bra can be adjusted tighter or looser [Hannah 4]
  • Thumbnail image #1 of Sieve Triangle Bra in Black [Aube 1]
  • Thumbnail image #2 of Sieve Triangle Bra in Black [Aube 1]
  • Thumbnail image #3 of Sieve Triangle Bra in Black [Aube 1]
  • Thumbnail image #4 of Sieve Triangle Bra in Black
  • Thumbnail image #5 of Sieve Triangle Bra in Black [Hannah 4]
  • Thumbnail image #6 of Sieve Triangle Bra in Black [Hannah 4]
  • Thumbnail image #7 of Sieve Triangle Bra in Black [Hannah 4]
Buy more, save money
Product photo #1 of Sieve Triangle Bra in Black [Aube 1] Product photo #2 of Sieve Triangle Bra in Black [Aube 1] Product photo #3 of Sieve Triangle Bra in Black [Aube 1] Product photo #4 of Sieve Triangle Bra in Black Product photo #5 of Sieve Triangle Bra in Black [Hannah 4] Product photo #6 of Sieve Triangle Bra in Black [Hannah 4] Product photo #7 of Sieve Triangle Bra in Black [Hannah 4]

Sieve Triangle Bra

Rated 4.4 out of 5
Based on 621 reviews

Surprising support. Deep v neckline.


Our signature Sieve mesh in a lower coverage triangle cut. 
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Free shipping over $100. Easy Returns.

Fit

  • Size Chart
  • Use this as a guide. Preference is a huge factor — the benefit of a non-wire is they're super flexible, so you will likely fit in more than one size. Like a looser band? Size up! Like less coverage? Size down! Still unsure? Try two sizes :)
  • Adjustable straps and hook & eye closure in the back
  • *Note, our Sieve Triangle Bra is an intentionally lower coverage in both the cups and the sides. Wide plush elastic band is extremely adaptable.

Fabric + Care

  • Size Chart
  • Made from a sheer Belgian power micromesh — nipples are visible
  • 74% Polyamide (Nylon) 26% Elastane (Spandex)
  • Hand wash in cold water, dry flat

FAQ

  • All unworn items, with tags attached and in their original packaging are eligible for return or exchange within 30 days of placing your order.
  • Please note, packs must be returned in full. We do not accept partial returns of packs.
  • Want to know our full returns policies? Here you go.
  • Want more info about shipping, materials or care instructions? Here!

    Q’s on fit or sizing? Email us at hello@negativeunderwear.com

Pair it with ->

Sieve High-Waist Brief in Black Sieve High-Waist Brief in Black Sieve High-Waist Brief in Black $45 +
Only a few left!
Whipped Boy Short in Black Whipped Boy Short in Black Whipped Boy Short in Black $45 +
Sieve Thong in Black Sieve Thong in Black Sieve Thong in Black $32 +
Cotton Mini Boy Short in Black Cotton Mini Boy Short in Black Cotton Mini Boy Short in Black $45
Write a Review
average rating 4.4 out of 5
Based on 621 reviews
  • 5 Stars
    433 Reviews
  • 4 Stars
    76 Reviews
  • 3 Stars
    62 Reviews
  • 2 Stars
    34 Reviews
  • 1 Star
    16 Reviews
88% of reviewers would recommend this product to a friend
Overall
Rated -1 on a scale of minus 2 to 2, where minus 2 is Hated it, 0 is Meh and 2 is Loved it
Quality
Rated 4 out of 5
Comfort
Rated 4 out of 5
621 Reviews
Reviewed by Steel
Verified Buyer
Review posted
Sieve Triangle Bra in Buff + Black
Reviewing
Sieve Triangle Bra in Buff + Black
I recommend this product
Rated 5 out of 5
Size Purchased
5
How it Fits
A Little Small
Age Range
45 - 54
Bra Size
38C

Beyond Comfortable with Perfect Suport

This bra is beyond comfortable and so breathable which is so important with everything I put on my body. With the summer heat and humidity for me less is better and I love that I still get the support I need. I would love this bra in soft pinks, and lavenders and baby blues.

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Overall
Rated 2 on a scale of minus 2 to 2, where minus 2 is Hated it, 0 is Meh and 2 is Loved it
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Was this helpful?
Reviewed by Jane B.
Verified Buyer
Review posted
Sieve Triangle Bra in Peach
Reviewing
Sieve Triangle Bra in Peach
I don't recommend this product
Rated 2 out of 5
Size Purchased
3
How it Fits
Runs Small
Age Range
55 - 64
Bra Size
38B

My mistake being excited for a discount

I was so excited to see a sale I didn't consider the fine print. The size guide said I would be a three, I wasn't sure between a 2 and a 3...so I bought both assuming I could exchange the wrong size. Well note that came with it said all sakes final. The 3 is also too small! I had to buy a bra extension to even make it work. Then I measured my regular size 38 with the 3.... MUCH smaller! I think I'd have to use two extenders to make the size 2 work.

I do like the bra in general, but think the size is so off that I'm not sure how anyone gets the right size. I want to say I'd maybe recommend this bra, but I'm not given that choice

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Overall
Rated 0 on a scale of minus 2 to 2, where minus 2 is Hated it, 0 is Meh and 2 is Loved it
Quality
Rated 4 out of 5
Comfort
Rated 2 out of 5
Was this helpful?
Reviewed by Samantha S.
Verified Buyer
Review posted
Sieve Triangle Bra in Buff
Reviewing
Sieve Triangle Bra in Buff
I recommend this product
Rated 5 out of 5
Size Purchased
2
How it Fits
True to Size
Age Range
25 - 34
Bra Size
34C

Happiness in a Bra

Hate wires, hate padding, hate bras in general. So happy I found this company. My boobs look and feel great (and my partner loves the way the bra looks too which is a bonus!)

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Overall
Rated 2 on a scale of minus 2 to 2, where minus 2 is Hated it, 0 is Meh and 2 is Loved it
Quality
Rated 5 out of 5
Comfort
Rated 5 out of 5
Was this helpful?

Non-Wire Bra Sizing

Non-Wire Bra Sizing Size Chart

* Non-wire bra sizing can vary by preference and if you're toward the top of a size range and prefer more coverage, you may want to size up. For styles available in + sizes (designed with additional support details for our larger cup customers), we find DD's can be on the cusp - if you prefer more coverage and support, we suggest the + bra equivalent for your band size.

Q’s about sizing or fit? Email us at hello@negativeunderwear.com

@negativeunderwear