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

Sieve Triangle Bra

4.5
Rated 4.5 out of 5 stars
1,748 Reviews

Surprising support. Deep v neckline.

Our signature Sieve mesh in a lower coverage triangle cut. Great shape -no pad or wire included. Create a custom 2 Pack ->
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Free U.S. shipping on orders over $100. Easy returns.

Fit

  • Size Chart
  • Use this as a guide. Preference is a huge factor — if you’re near the top of a size range and/or prefer more coverage, you may want to size up.
  • Triangle cut has lower coverage in both the cups and the sides.

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 String Thong in Black Sieve String Thong in Black (alternate view) Sieve String Thong in Black $30
Cotton French Cut Brief in Black (Pack) Cotton French Cut Brief in Black (Pack) (alternate view) Cotton French Cut Brief in Black (Pack) $58 +
Whipped Boy Short in Black Whipped Boy Short in Black (alternate view) Whipped Boy Short in Black $45 +
Sieve High-Waist Brief in Black Sieve High-Waist Brief in Black (alternate view) Sieve High-Waist Brief in Black $45
4.5
Rated 4.5 out of 5 stars
Based on 1,748 reviews
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1,748 reviews
  • Kami H.
    Verified Buyer
    Size Purchased 3
    How it Fits True to Size
    Age Range 35 - 44
    Bra Size 36C
    3 minutes ago
    Size Purchased 3
    How it Fits True to Size
    Age Range 35 - 44
    Bra Size 36C
    Sieve Triangle Bra in Cherry
    Reviewing
    Sieve Triangle Bra in Cherry
    Rated 5 out of 5 stars
    Comfortable!

    This bra is so comfortable

    Was this helpful?
  • Ellen B.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 65+
    Bra Size 38C
    2 hours ago
    Size Purchased 5
    How it Fits True to Size
    Age Range 65+
    Bra Size 38C
    Sieve Triangle Bra in Buff
    Reviewing
    Sieve Triangle Bra in Buff
    Rated 5 out of 5 stars
    Bought the white boa and buff.

    Love the bras.

    Was this helpful?
  • Ellen B.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 65+
    Bra Size 38C
    2 hours ago
    Size Purchased 5
    How it Fits True to Size
    Age Range 65+
    Bra Size 38C
    Sieve Triangle Bra in White Boa
    Reviewing
    Sieve Triangle Bra in White Boa
    Rated 5 out of 5 stars
    Love the Sieve Triangle bra.

    The reduced cut is both comfortable and sensual. I’m a size 38C, sized up to a 5, glad I did.

    Was this helpful?
  • Kathleen S.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 18 - 24
    Bra Size 40C
    2 hours ago
    Size Purchased 5
    How it Fits True to Size
    Age Range 18 - 24
    Bra Size 40C
    Sieve Triangle Bra in Buff + White
    Reviewing
    Sieve Triangle Bra in Buff + White
    Rated 5 out of 5 stars
    Love!

    Super pretty and flattering

    Was this helpful?
  • Mallory D.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 25 - 34
    Bra Size 40C
    21 hours ago
    Size Purchased 5
    How it Fits True to Size
    Age Range 25 - 34
    Bra Size 40C
    Sieve Triangle Bra in Black
    Reviewing
    Sieve Triangle Bra in Black
    Rated 5 out of 5 stars
    Great alternative to underwire bras

    I tried this bra because I was looking for one that gave the same level of lift, but without an underwire, and this one did the trick! It is so comfortable and looks great.

    Was this helpful?
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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

Detail view of Sieve Triangle Bra in Black for sizer

@negativeunderwear