Built for changing conditions.
Shop HikingLove it
"I love it ! It is very comfortable.. i already had black ones and they stay in great condition as time goes by. Machine wash and hang up to dry is easy maintenance."
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Featuring a slim, modern fit and our corespun merino wool fabric, the Siren bra with inserts offers the support you need with a soft, sleek and stretchy construction.
Good for:

Main Body: 83% Merino Wool, 12% Polyamide, 5% Elastane; Mesh:Inner: 92% Polyamide, 8% Elastane; Lining: 83% Merino Wool, 12% Polyamide, 5% Elastane; Exclusive Of Decoration And Elastic
Machine Wash Warm. Wash Inside Out With Like Colors. Do Not Use Softener. Do Not Bleach. Do Not Tumble Dry. Line Dry In Shade. Warm Iron. Do Not Iron Print And Accessories. Do Not Dry Clean.
Model measurements
Height: 172cm / 5' 8".Waist: 60cm / 24".Amande is wearing size S
Key product measurements
Back High Point Shoulder to Hem: 5.5cm (Based on size M)
Fit
Slim
The Siren is a lightweight next-to-skin layer. It’s crafted from 150gm merino jersey corespun fabric that’s lighter than most other fabrics we use, and is made with a snug, slim fit that works perfectly as a cosy piece beneath your other layers. Our Siren tees fit tighter than other tees in our range, just size up if you like a looser fit.
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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: 4.503268 / 5 from 153 reviews.
The Women's Merino 150 Siren Bra is designed for comfort and ease of layering. Customers appreciate its soft, odor-resistant fabric and its ability to regulate body temperature. While opinions vary on the fit, comfort, and support, the bra's feel and color are highly praised.
Review topics: ["fit","size","quality","price","feel","looks","material","bra","straps","band","padding","colour","wear","shape","fabric","support","medium","weather","comfort","buy","design","model","smell","inserts","fibers","wool","drying","label","wash","activities"].
"I love it ! It is very comfortable.. i already had black ones and they stay in great condition as time goes by. Machine wash and hang up to dry is easy maintenance."
— Slime (5/5)
"Finding a merino bra that has a good fit and that is also comfortable has been a challenge but this 150 Siren bra delivers well in all areas. The fit is nice with good coverage and adjustable shoulder straps. It has low/medium support which is what I was looking for in this type of bra. My only suggestion where it has room for improvement is the removable pads. I do like the option to have pads that are removable, however the pads that come with this bra have an awkward texture/shape to me that doesn’t give a smooth look. So I will most likely be wearing without the pads or replacing with a different set of pads. Overall I’m very pleased with this bra and would recommend."
— Valerie (5/5)
"Great for hot weather and hot flashes. Pack for recent road trip. Dried fast. Nude color great for white tops. Very comfy."
— TreeYoga (5/5)
"I have several of these bras and they are great! I’m a huge fan of wool and they are my every day work bras. Fairly comfortable and low profile, don’t make me feel smashed like sports bras. You can wear them multiple times between washes. I bought this one because all my others were black and needed a nude color under a bridesmaids dress."
— Hannah H. (5/5)
"Perfect nude color for wearing under white clothing. All the benefits of merino. Plan to wear to hot humid locations. Enough support for yoga, day hikes."
— Tree Y. (5/5)
"Love these bras, I've got several and they've lasted so well. The quality is excellent"
— Zozz (5/5)
"The best bra ever! I wear these all the time and have them in so many colors. It's so soft and has the best support for a bralette. I love that they come with padding, so I can either use them or take them out."
— Sofi (5/5)
"I like the bra, but hate the labels. Used to take them out but not this time because they sewed them together with the seam. Come on, is it necessary to have so many labels? They’re so itchy."
— Yu-hui L. (1/5)
"J'ai longtemps hésitée mais je ne suis pas déçue par ce soutien-gorge Siren. Plutôt confortable, le maintien me convient pour un 95 B. La couleur Summit est jolie, la coupe est flatteuse. Je ne mets pas pour l'instant les inserts, quoique assez discrets par leurs épaisseurs, je verrais aux beaux-jours. Je recommande, pour celles qui recherchent un soutien-gorge sans armature pour ses matières naturelles."
— Valérie (5/5)
"I love these bras!! I have them in multiple colors. They are durable and easy to clean. I love that you can wear them multiple times without worrying about odors, perfect for travel."
— Lars (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.
| Measurements | Cup size | Comparable Bra size |
|---|---|---|
|
Under bust 26In Bust Circumference 32In |
XS - 30B | 30 A,B,C - 32 A,B |
|
Under bust 28In Bust Circumference 34In |
S - 32B | 32 B,C,D - 34 A,B |
|
Under bust 30In Bust Circumference 37In |
M - 34B | 34 B,C,D - 36 A,B |
|
Under bust 32In Bust Circumference 39In |
L - 36B | 36 B,C,D - 38 A,B |
|
Under bust 34In Bust Circumference 42In |
XL - 38B | 38 B,C,D - 40 A,B,C |
| Measurements | Cup size | Comparable Bra size |
|---|---|---|
|
Under bust 68cm Bust Circumference 82cm |
XS - 30B | 30 A,B,C - 32 A,B |
|
Under bust 73cm Bust Circumference 88cm |
S - 32B | 32 B,C,D - 34 A,B |
|
Under bust 78cm Bust Circumference 94cm |
M - 34B | 34 B,C,D - 36 A,B |
|
Under bust 83cm Bust Circumference 100cm |
L - 36B | 36 B,C,D - 38 A,B |
|
Under bust 88cm Bust Circumference 107cm |
XL - 38B | 38 B,C,D - 40 A,B,C |
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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