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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
1,744 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 1,744 reviews
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1,744 reviews
  • Mallory D.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 25 - 34
    Bra Size 40C
    3 minutes 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?
  • Jennifer J.
    Verified Buyer
    Size Purchased 3
    How it Fits True to Size
    Age Range 35 - 44
    Bra Size 34DD/E
    11 hours ago
    Size Purchased 3
    How it Fits True to Size
    Age Range 35 - 44
    Bra Size 34DD/E
    Sieve Triangle Bra in Slate
    Reviewing
    Sieve Triangle Bra in Slate
    Rated 5 out of 5 stars
    Well worth it!

    I really love this bra. I have a band measurement of 34”, and a chest measurement of 39” and chose sz 3. I could have probably gone with a 4 and been comfy, but the 3 fits well, supports great and doesn’t squish down my chest. The fabric is soft and the band sits well without digging in or riding up.

    Was this helpful?
  • Tamlya E.
    Verified Buyer
    Size Purchased 1
    How it Fits True to Size
    Age Range 55 - 64
    Bra Size 34B
    Yesterday
    Size Purchased 1
    How it Fits True to Size
    Age Range 55 - 64
    Bra Size 34B
    Sieve Triangle Bra in Black
    Reviewing
    Sieve Triangle Bra in Black
    Rated 5 out of 5 stars
    Most comfortable bra ever

    I was about to give up wearing one altogether until I found Negative. This is a supremely comfortable bra with NO WIRES! Much more supportive than any bralette and classy. Very classy.

    Was this helpful?
  • Angie M.
    Verified Buyer
    Size Purchased 3
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 34C
    Yesterday
    Size Purchased 3
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 34C
    Sieve Triangle Bra in Coral + White
    Reviewing
    Sieve Triangle Bra in Coral + White
    Rated 5 out of 5 stars
    Comfortable

    Loved this new style. Wasn’t sure about the clasp in back as I have gone to not having them but was very comfortable

    Was this helpful?
  • Sarah L.
    Verified Buyer
    Size Purchased 1
    How it Fits True to Size
    Age Range 25 - 34
    Bra Size 32C
    6 days ago
    Size Purchased 1
    How it Fits True to Size
    Age Range 25 - 34
    Bra Size 32C
    Sieve Triangle Bra in Buff
    Reviewing
    Sieve Triangle Bra in Buff
    Rated 5 out of 5 stars
    Great bra

    This is my first time trying Negative bras, and they really live up to the hype! Great quality and very supportive. I decided to go with the glace material instead of the sieve as I am planning to wear this with white shirts and want a bit more coverage around the nip area.

    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

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