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Icebreaker Women's Siren Merino Wool Bikini Underwear

  • Based on 263 reviews
Condition: New
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Availability: Only 1 left in stock, order soon!
Fulfilled by Amazon

Arrives Tuesday, Sep 2
Order within 23 hours and 45 minutes
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Size: X-Small


Color: Black/Black


Features

  • 83% Merino Wool, 12% Nylon, 5% Lycra elastane
  • Imported
  • Machine Wash
  • WOMEN'S WOOL BIKINI UNDERWEAR: Perfect for daily wear or kicking back after a long day outside, this stretch-blend underwear features a flattering slim fit and forward set seams for all-day comfort
  • WOOL UNDERWEAR FOR WOMEN: This wool bikini brief features jersey corespun fabric & nylon fibers for added strength, durability & next to skin softness Crafted of 83% merino wool, 12% nylon, 5% elastane
  • MERINO WOOL LAYERS: Stay warm from head to toe in Icebreaker outdoor clothing gear Keep heads covered on the mountains, slopes, trials & lakeside with wool beanies, balaclavas, scarves, chutes & headbands
  • WOOL & CASUAL: Whether skiing, camping, hiking or daily wear, Icebreaker provides clothes for men, women & children - keeping the whole family covered in jackets, beanies, scarves, sweaters, pants, leggings, underwear & more wool clothing
  • ICEBREAKER LONGEVITY: We use 85% merino wool & less synthetic material than the traditional outdoor standard With multi-purpose & timeless clothing our natural alternative to synthetics enhances the relationship between people & nature

Department ‏ : ‎ womens


Date First Available ‏ : ‎ July 22, 2019


Frequently asked questions

If you place your order now, the estimated arrival date for this product is: Tuesday, Sep 2

Yes, absolutely! You may return this product for a full refund within 30 days of receiving it.

To initiate a return, please visit our Returns Center.

View our full returns policy here.

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Top Amazon Reviews


  • 4.0 out of 5 stars Small bikini
Size: X-Large Color: Gritstone Hthr
I love the cut and fabric of Icebreakers merino undies. They are pretty durable and will survive if accidentally washed and dried in a normal cycle. The bikini style is a little small, and fits like an itty-bitty bikini and slides under my mom pooch. The hipkini style seems to run more true to size and gives a little extra coverage without feeling or looking like granny panties. ... show more
Reviewed in the United States 🇺🇸 on February 10, 2023 by G. Watson

  • 2.0 out of 5 stars Big difference in cut and fit between sizes
Size: Medium Color: Black/Black
I bought a size large according to the size chart. I usually wear a medium. I decided I would go by the chart because these underwear are very expensive. When I tried them on, they were too big and baggy in the butt. I decided to try a medium as I have an upcoming packing trip in the mountains. When I received the medium, they were cut much smaller. I would say a small to extra small. They didn't cover my butt and they were very low on the hips. I am 5'6 and 146 lbs. I don't have big hips, nor am I a pear shape. These underwear are way too expensive to have such a huge difference in cut and fit, from a large to a medium. Very disappointed. I was hoping they would work for me. The material is also thinner than I had expected. ... show more
Reviewed in the United States 🇺🇸 on May 15, 2023 by J. Trabucco

  • 4.0 out of 5 stars Over priced
Size: Medium Color: Gritstone Hthr
Decent fit, but a little too expensive for what they are.
Reviewed in the United States 🇺🇸 on November 14, 2022 by meghan

  • 5.0 out of 5 stars Wife loves these
Size: Large Color: Gritstone Heather
My wife’s favorite pair of underpants. As an active hiker she has nothing but positive to say about them. I’ve bought her multiple pairs at this point
Reviewed in the United States 🇺🇸 on November 3, 2022 by Dave C

  • 5.0 out of 5 stars My favorite underwear
Size: X-Large Color: Gritstone Hthr
If you haven't tried wool underwear, give it a shot. These are my favorite. Very comfortable, breathable & these last a long time. Great for everyday and/or travel, camping, hiking, etc ...
Reviewed in the United States 🇺🇸 on September 29, 2022 by Danielle Creedon

  • 5.0 out of 5 stars Comfort and function
Size: X-Small Color: Kingfisher
These are super comfortable and well made. Saw other reviewers mention a lack of coverage. They seem to have the same amount of coverage as any other style bikini like Victoria Secret. No, they aren’t granny panties. The boy shorts or the meld have full coverage. I have several pairs of both of those. Sometimes you need different styles for different activities. I like these for running and the boy shorts for hiking. Again, everyone is different and underwear is a very personal thing! What works for one won’t for another. I did worry that the xs might be too small after reading the reviews but it’s perfect for me. I’m 5’3” and 113 w/ a very athletic build and yes, I have a backsides what gets me up hills. All I can say is try them and see! ... show more
Reviewed in the United States 🇺🇸 on December 27, 2019 by Turtle

  • 3.0 out of 5 stars Did not cover bottom
Size: X-Small Color: Stripe/Eggplant/Silk Heather
Since Ibex announced they were going out of business, I have been trying to find a replacement for my favorite cut of wool underwear. I hesitantly tried Icebreaker again even though I remembered a year or so ago reading that the quality wasn't great. These are a much thinner material than the Ibex briefs were and thinner than the Smartwool PhD Seamless bikini. I don't think they felt cheap, but I would be interested to see how that held up over time. I am about 5' 4" and 120lbs. and found the X Small was a bit too small. I would have been willing to try them in a size up, however I hated the cut. These did NOT cover my butt and I kept having to adjust them while I was trying them on, which tells me they would just ride up a ton while wearing them out. They had more of a "cheeky" cut that I just don't care for and I have a pretty flat bottom. These went back. ... show more
Reviewed in the United States 🇺🇸 on February 4, 2018 by Jess

  • 4.0 out of 5 stars Lightweight, everyday panty
Size: Small Color: Black/Black
I love this thinner, lightweight bikini for everyday use -- especially in warm weather. There is not much rear coverage, and they can ride up a bit but not much. If you are curvy, you may want to size up. If you want full coverage, get the Sprite Hot Pant; it's a thicker material. If you want no coverage, get the Siren Thong (but order a size up on those -- they run small and tight). The bikini is somewhere in between. Amazon, or better Icebreaker, would do well to provide back-view photos with a human model so we could actually see the coverage. My two cents. ... show more
Reviewed in the United States 🇺🇸 on June 29, 2017 by Bunbury3

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