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[Aube 1]
[Aube 1]
[Aube 1]
Wide elastic bland is comfortable and supportive
[Hannah 4]
[Hannah 4]
[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] Product photo #7 of Sieve Triangle Bra in Black [Hannah 4]

Sieve Triangle Bra

Rated 4.5 out of 5
228 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 21 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

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Write a Review
average rating 4.5 out of 5
Based on 228 reviews
  • 5 Stars
    158 Reviews
  • 4 Stars
    32 Reviews
  • 3 Stars
    31 Reviews
  • 2 Stars
    5 Reviews
  • 1 Star
    2 Reviews
91% of reviewers would recommend this product to a friend
228 Reviews
Reviewed by Robin L.
Verified Buyer
Sieve Triangle Bra in Black
Reviewing
Sieve Triangle Bra in Black
I recommend this product
Rated 5 out of 5
Review posted

I f-ing love it

I absolutely love this bra, it’s so comfortable with the right amount of sexy. I can’t go back to wired and padded uncomfortable bras. Do yourself a favor and buy this bra, your boobs will thank you!

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Reviewed by Ory M.
Verified Buyer
Sieve Triangle Bra in Black
Reviewing
Sieve Triangle Bra in Black
I recommend this product
Rated 5 out of 5
Review posted

Only Bra I Wear

I am a 30D--so finding a bralette is next to impossible for me but this one is as close to perfect as it gets! I ordered a size 1 in both the Sieve non-wire bralette and the Sieve Triangle and i will be honest i like the Sieve Triangle better. This bra is comfy enough to sleep in and sexy enough to wear on a date. I am probably going to order a second one soon because i just wear this one so much! If you have a small ribcage and bigger breasts this is a bralette worth trying!!!! It is seriously one of the only ones that works for my size. The only recommendation i would make would be to make one more set of hooks on the back because i feel like over time i will need to tighten it. Highly recommend!

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Reviewed by Jamie G.
Verified Buyer
Sieve Triangle Bra in Peach
Reviewing
Sieve Triangle Bra in Peach
I recommend this product
Rated 5 out of 5
Review posted

Perfection

I have a black size 2, fits well a little loose but comfortable. So I got this peach in a size 1 for a snugger fit. They’re both fantastic, I wear either one or the other depending on the color of my top. I’m a 32D/32C so I’m in between sizes, so it fits their chart perfect. 5’2 115lbs. I’m petite so the size 1 cup sits lower on my chest if I wanted a low cut shirt this would be the one I’d go to.

LOVE. I literally don’t wear anything else. And I’m very active in my profession- no slips, I forget I’m wearing it.

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Non-Wire Bra Sizing

Size Chart

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

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