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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
1,750 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 1,750 reviews
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1,750 reviews
  • Susan K.
    Verified Buyer
    Size Purchased 5+
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 38DD/E
    3 minutes ago
    Size Purchased 5+
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 38DD/E
    Sieve Triangle Bra in Buff
    Reviewing
    Sieve Triangle Bra in Buff
    Rated 5 out of 5 stars
    Best BRA EVER

    do not feel like I am wearing one!!!

    Was this helpful?
  • Karen T.
    Verified Buyer
    Size Purchased 5
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 38DD/E
    20 minutes ago
    Size Purchased 5
    How it Fits True to Size
    Age Range 45 - 54
    Bra Size 38DD/E
    Sieve Triangle Bra in Black
    Reviewing
    Sieve Triangle Bra in Black
    Rated 5 out of 5 stars
    Amazing

    Unbelievably comfortable, super cute and the straps stay on my shoulders! There are no other non-racerback bras that stay on my shoulders this well. Sizing was spot on - I love that there are no measurements, you're a number 1-5. LOVE!

    Was this helpful?
  • Kami H.
    Verified Buyer
    Size Purchased 3
    How it Fits True to Size
    Age Range 35 - 44
    Bra Size 36C
    Yesterday
    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
    Yesterday
    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
    Yesterday
    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?
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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