Icebreaker Women's Siren Bra - Mountain Steals
Gritstone Heather

Women's Siren Bra

Icebreaker Women's Siren Bra is rated 4.4 out of 5 by 411.
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4.4 Star Rating
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The Icebreaker Women's Siren Bra is a stretchy bra for breathable, comfy support. Made with Merino CoreSpun fabric, the merino wool, nylon and elastane, the ultralight weight is ready for all times of year. Temperature regulation through all seasons in light support for days on the couch, your yoga practice and so much more. The all day, every day option.

Products on Sale are Discontinued Styles or Colors.

Product Description
Item No.   10303167

FEATURES of the Icebreaker Women's Siren Bra

  • Corespun fabric for enhanced durability
  • Sleek design for everyday comfort and layering
  • Adjustable straps
  • No side seam construction
  • Icebreaker tonal screenprint logo

Product Specifications
Primary Fabric: Merino Wool
Gender: Womens
Features: Adjustable, Quick Drying, Merino Wool
Sustainability: Animal Friendly, Eco-friendly
Fabric Weight: 4.42 oz / Square Yard
Disclaimer: We only ship this brand to US Addresses.
Best Use: Athleisure, Casual, Fitness
Fit Type: Skin Tight
Product Reviews
Rated 4 out of 5 by from Almost Perfect I am a lean 54 year old woman with a large ribcage and modest breasts, so this kind of bra suits me well. Although I could have probably worn a Small I went with the Medium, as I do not like to have the elastic digging in o my body all day. The reason for 4 stars versus 5 is the location of the adjustment system on the front rather than the back of the straps. The little bracket hits me just below the collar bones and is smashed there by my backpack straps. I did a little sewing modification and repositioned the adjusters on the back, which is where they belong in my opinion. Materials and craftsmanship are excellent and I bought a 2nd bra immediately!
Date published: 2022-03-23
Rated 3 out of 5 by from No longer comes with padded inserts I've owned the older version of this bra for several years and I love it for informal/non-athletic activities. It's comfortable, it's functional, it's well-made. So I ordered a couple new ones. They're still comfortable, functional, and well-made, BUT - big but! - it used to come with padded inserts. That is no longer true. You have to read the description closely to catch the change - it includes space to put in padded inserts, but not the inserts themselves. Not really sure why they would do this? In my experience, the inserts were a major "pro" to this bra over similar items from other companies. I'm bummed, it's a significantly less useful product now.
Date published: 2021-01-12
Rated 3 out of 5 by from Quick dry The thing I like best is the fact that the wool dries quickly. I have a B cup. Any larger than a C and don’t think this would contain your ta-tas. Design things I think could be improved: -Top corner of the cups pucker. Perhaps because I’m small chested. - the straps are jusssst a bit to narrow for my taste. - the width of the material under the arms is a little narrow and if you’re not totally trim, you get the little fat roll squish. - I’m a solid 38” around so the L should fit but I imagine an XL would have been less snug. All that aside, I’m going to keep wearing but won’t buy again.
Date published: 2022-06-15
Rated 4 out of 5 by from Mostly love it I am a 36D and purchased a medium. The fit of this bra is not perfect, but I do like it. I tend to come out of the cups a bit if I am doing a lot of bending or lunging, so I would consider this just a casual bra. The band fits perfectly but the cups are just slightly too small. It does give me great cleavage and makes me feel less disheveled than my other lounge bras, so that’s a positive. I am happy I purchased this bra on sale because I would not feel completely happy with it at full price, but I am glad I didn’t miss out on trying this one. I would recommend this bra with the knowledge that it is not ideal for more than casual wear due to the cup coverage.
Date published: 2021-12-31
Rated 4 out of 5 by from For those with larger boobs This is a great product made with excellent material therefore making the bra extremely comfortable. I would recommend this bra to those who have smaller breasts. I bought and returned this bra because my 34 C boobs did not fit. I had problems with boob "spillage" out of the sides of the bra. I also found when I put on a shirt, you could see the bra line on the front. Lastly, this bra is very thin and is not padded. Although I was fine with that, it is important to point out. There are openings to add your own padding but it is not provided. Overall, great product but not for me.
Date published: 2016-10-09
Rated 1 out of 5 by from Disappointed I love merino clothing so I was hoping to get a comfortable bra that would help with my fibromyalgia pain and sweats. I went by the recommended size and it's way too small. I bulge out the sides and fall out the front. I was also disappointed that the straps and band on the bottom aren't merino, but basically the same sweat inducing type of elastic that's on my other bras. This is the most expensive bra I've ever bought and feel it was a total waste of money. I don't even want to try a larger size because of the elastic. For reference, this is the first time I've ever left a negative review because I'm generally easy to please, but I'm very disappointed.
Date published: 2021-07-23
Rated 4 out of 5 by from Easy Care for Long-Term Travel, but Durable? Bought 2 siren bras for a 10 month hiking RTW trip. They do well being hand washed and dry quickly. I think they'll be a great staple as long as they last. Since I am carrying so few clothing options, all of the clothes I have get intensive use. Unfortunately, I recently heard from another traveler that her siren bra fell apart in her first few months on the road!! I'm hoping that on my somewhat smaller frame I won't have the same experience. I am a 34B and purchased a small. It's a good fit and after the first couple of washes, still retains its shape. It is snug, but very comfortable and breathable. As long as they last, I'll be very pleased with this purchase.
Date published: 2016-08-28
Rated 4 out of 5 by from Icebreaker Siren Bra The Icebreaker Siren Bra, though not perfect, is without a doubt the best bra that I own. The merino breathes well in summer, dries quickly, and feels "cleaner" than the underwire bras I wore before. I've been equally happy in winter months with the Siren Bra, which does insulate some. I ordered the XS based on my 32B bra size, and it's a very comfortable fit. The band is quite snug, but not constricting. It would be nice if the band was a little softer and if the cups were just slightly shorter so that they worked with a camisole, but overall, the merino itself and the minimalist yet flattering construction make this item a winner!
Date published: 2018-09-03
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Size Guide

Icebreaker Womens Base Layers

SIZE X-Small Small Medium Large X-Large
Bust 30 - 32" 32 - 34" 34 - 37" 37 - 40" 40 - 42"
Arm Length 30.25 - 30.5" 30.05 - 30.75" 30.75 - 31" 31 - 31.25" 31.25 - 31.5"
Waist 24 - 26" 26 - 22" 28 - 30" 30 - 32" 32 - 35"
Hip 34 - 36" 36 - 38" 38 - 40" 40 - 42" 42 - 44"

Chest / Bust: Measure around the fullest part of the chest, keeping the tape parallel to the floor.

Waist: Measure around the narrowest point, keeping the tape parallel to the floor.

Hip: Stand with feet together and measure around the fullest point of the hip, keeping the tape parallel to the floor.

Arm Length: Measure from shoulder (Humerus) to wrist.

SLIM FIT: A snug, close-to-body fit for low bulk layering.

REGULAR FIT: Neither snug or loose. These garments can be worn solo or over other layers.

RELAXED FIT: Loose fitting lightweight layers.