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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]
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]
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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]

Sieve Triangle Bra

Rated 4.4 out of 5
Based on 733 reviews

Surprising support. Deep v neckline.


Our signature Sieve mesh in a lower coverage triangle cut. Great shape - no pad or wire included. 
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Free shipping for the holidays. 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)
  • Wireless
  • Hand wash in cold water, dry flat

FAQ

  • All full-priced, 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 +
Cotton French Cut Brief in Black (Pack) Cotton French Cut Brief in Black (Pack) Cotton French Cut Brief in Black (Pack) $58 +
Whipped Boy Short in Black Whipped Boy Short in Black Whipped Boy Short in Black $45 +
Essaouira Thong in Black Essaouira Thong in Black Essaouira Thong in Black $30 +
Write a Review
average rating 4.4 out of 5
Based on 733 reviews
  • 5 Stars
    514 Reviews
  • 4 Stars
    86 Reviews
  • 3 Stars
    75 Reviews
  • 2 Stars
    38 Reviews
  • 1 Star
    20 Reviews
88% of reviewers would recommend this product to a friend
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 4 out of 5
733 Reviews
Reviewed by Susan L.
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
2
How it Fits
True to Size
Age Range
55 - 64
Bra Size
34DD/E

Sieve set

Love the thong, super sexy and very comfortable. Love it!

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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 JI
Verified Buyer
Review posted
Sieve Triangle Bra in Navy
Reviewing
Sieve Triangle Bra in Navy
I recommend this product
Rated 3 out of 5
Size Purchased
3
How it Fits
A Little Small
Age Range
35 - 44
Bra Size
34DD/E

Not great for big-busted babes, less breathable and comfortable than expected

Don't get me wrong, this is a sexy bra, but it does not resolve the bubble boob problem I often have with bralettes (I'm a 34DD). I even sized up to a size 3 (previous bralette purchased from Negative was a size 2) and still find my boobs popping out. I also thought this would be better for sweat given that it is mesh, but sadly it's not.

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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 Jena H.
Verified Buyer
Review posted
Sieve Triangle Bra in Buff + White
Reviewing
Sieve Triangle Bra in Buff + White
I recommend this product
Rated 5 out of 5
Size Purchased
4
How it Fits
True to Size
Age Range
25 - 34
Bra Size
34DDD/F

Amazing!

My second one and still great! I am determined to collect all of the colors!

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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.

Btw, the size nomenclature has changed for Bra Tops. Here's the conversion:
XS=0, S=1, M=2, L=3, XL=4, XXL=5

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

@negativeunderwear