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"Love the shape, the quality is fantastic. The green is such a lovely green. Really muted and soft"
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$54.99
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$54.99
This item's price has been updated recently to ensure you get the best value.
Dernier prix -
The Merino 150 Siren Bikini is stretchy and soft next to your skin, a slim-fit underwear for go-to everyday comfort. The Siren's lightweight Merino Corespun fabric is naturally odour resistant and helps regulates body temperature in all weather conditions.
Good for:

83% Merino Wool, 12% Polyamide, 5% Elastane; Exelusive of Elastic
Machine wash warm. Wash inside out with like colors. Do not use softeners. Fasten all closures to wash and dry. Do not bleach. Do not tumble dry. Line dry in shade. Warm iron. Do not iron print, trims and accessories. Do not dry clean.
Model measurements
Height: 178cm / 5'10". Waist: 61cm / 24". April is wearing size S.
Key product measurements
Height: 24.2cm (based on size S); Width: 33.0cm (waist width, size S)
Regular Fit
Slim
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Merino wool neutralizes unpleasant odors by absorbing odour molecules into its fibers, making them less detectable by the human nose.
Merino fibers efficiently manage moisture, absorbing it from your skin and releasing it into the atmosphere. It can absorb up to 35% of its weight in water without feeling wet.
icebreaker merino wool garments undergo special anti-shrinkage treatment, helping to resist deformation and pilling.
The thermo-regulation properties of merino wool adapt to your body and external conditions, so you can stay warm in the cold and cool in the heat.
Overall rating: 4.634021 / 5 from 582 reviews.
The Women’s Merino 150 Siren Bikini is praised for its soft, durable, and comfortable fabric. Customers appreciate the variety and vibrancy of the colors, as well as the great fit and look of the product. However, opinions vary on the coverage and size, with some recommending going a size up.
Review topics: ["fit","size","model","coverage","weight","weather","fabric","colour","quality","delivery","material","price","looks","feel","design","value","wear","comfort","style","works","moisture","shape","medium","pants","pattern","cotton","summer","underwear","waist","durability"].
"Love the shape, the quality is fantastic. The green is such a lovely green. Really muted and soft"
— Zozz (5/5)
"These are awful. I have probably a dozen pairs of Icebreaker bikini & hipkini briefs. I love their breathability, but have always been frustrated by how quickly they develop holes. This is the worst pair I've had by far (passion color, 150 merino). They developed a number of holes on the first wash."
— Lina H. (1/5)
"I purchased the Women’s Merino 150 Siren Bikini for my wife, and she absolutely loves them. The merino wool is incredibly soft and breathable—nothing like traditional wool that can feel itchy. They’re lightweight, comfortable, and perfect for everyday wear, whether at home, traveling, or layering for outdoor adventures. She especially appreciates how well they regulate temperature and wick moisture, keeping things fresh throughout the day. The fit is flattering and stays in place without digging in or bunching up. They also wash and wear really well, maintaining their shape and softness over time. Icebreaker has really mastered comfort and practicality with this design. Highly recommended for anyone looking for premium-quality, natural-fiber underwear that feels as good as it performs."
— Joshua N. (5/5)
"Most comfortable underwear ever."
— Ashley (5/5)
"My favorite briefs!"
— Ingrid K. (5/5)
"Featherlight and warm!"
— Sibylle Z. (5/5)
"perfect"
— Johanne B. (5/5)
"I've been wearing Icebreaker bikini underwear for years and can't imagine ever wearing anything else."
— Goody (5/5)
"I was hesitant about merino wool at first but have become the biggest fan! Perfect for a hike or everyday wear"
— Ash (5/5)
"It's August in New York City, and between the humidity, heat, and summer thunderstorms, it was feeling swampy outside - and in my pants. I decided to depart from my go-to synthetic seamless VS bikini bottoms and try these. I followed the size chart: I am a 36. 5"" hip, I went with the Small. (I am a XS in VS) I like my underwear snug, I like a high cut leg with thin sides, I don't like VPL. These passed the test. I could wear these with a lacy bra and you couldn't tell they were wool underwear. Nice thin material, breathable. Looking forward to wearing these all year-round."
— Christina (5/5)
Find the size that fits you best based on people just like you.

Use the chart below to determine your size. If you’re between two sizes, order the smaller size for a tighter fit or the larger size for a looser fit. If your measurements for chest and waist correspond to two different sizes, order the size indicated by your chest measurement for tops and your hip measurement for pants.
Sizing charts:
| XS | S | M | L | XL | |
|---|---|---|---|---|---|
| Waist | 24-26 | 26-28 | 28-30.5 | 30.5-33 | 33-36 |
| Hip | 33.5-35.5 | 35.5-38 | 38-40 | 40-42.5 | 42.5-45 |
| XS | S | M | L | XL | |
|---|---|---|---|---|---|
| Waist | 61-66 | 66-71 | 71-77 | 77-84 | 84-91 |
| Hip | 84-90 | 90-96 | 96-102 | 102-108 | 108-114 |
*Looking for the inseam length? Please refer to the product page to find out.
Our three different fits - slim, regular, and relaxed - ensure that when worn together, layers move and breathe like a single garment.



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