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€49,95
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€49,95
Our best-selling bra with a comfortable and lightly supportive fit, the Siren Bra features our 150gm jersey corespun fabric, which uses merino wool fibers wrapped around a nylon core for added strength and durability, while retaining next-to-skin softness. We've added a touch of LYCRA® for active stretch. The Siren’s sleek design and no-side-seam construction is perfect for everyday comfort and easy layering, while its thin adjustable elastic straps make for a barely-there feel.
Good for:
83% Merino Wool/ 12% Nylon/ 5% Elastane, Exclusive of decoration
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:91cm / 35". Amande is wearing size S.
Key product measurements:
Height: 4.9cm (front height, based on size S); Width:29.8cm (bottom opening width, size S)
Slim Fit
A snug, close-to-body fit for low bulk layering.
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.
Standard delivery: free for all order over £ 40. Delivery in 5-7 days, from Monday to Saturday, during working hours.
Please visit our Delivery page and find out more about the ways in which you can receive our products.
You have 30 days from delivery to follow our quick and easy return procedure.
Overall rating: 4.4026647 / 5 from 1351 reviews.
The 150 Siren Bra offers a comfortable and supportive fit suitable for various activities. The fabric is soft and breathable, providing a great feel against the skin. While opinions vary on the band, cups, and straps, the overall design is sleek and easy to layer.
Review topics: ["fit","size","delivery","price","weight","quality","feel","problem","looks","material","band","bra","straps","fabric","padding","support","wear","shape","comfort","cups","medium","design","weather","colour","style","top","model","buy","layer","summer"].
"Purchased two of these bras in May of 2026 and have worn each no more than ten times. I've washed by hand and hung to dry. Already, the elastic band is showing signs of wear with the elastic kinda breaking apart in the gray one (black one looks fine). Very disappointed in the quality. Bought a medium and I am 4'11"/110 lbs."
— Liz (2/5)
"The sizing chart made getting the right fit easy. My recommended size medium is snug under the bust without being tight and I forget I am wearing it. I like the front positioned strap adjustment. The plunge style does offer a challenge in keeping things in place when active. I took away one star for this."
— AJD (4/5)
"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)
"Seamless and comfortable wear, perfect size, nice material, breathing and soft."
— Baiba (5/5)
"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)
"Toujours aussi confortable. Les sous vêtements mérinos sont une première première couche parfaite été comme hiver. Le choix de couleurs varie selon les saisons, parfait pour ajouter à ma collection."
— M (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)
Find the size that fits you best based on people just like you.
Height: 172cm / 5'8". Waist:91cm / 35". is wearing size S.
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.
| XXS | XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|---|
| Bust | 27.5-30 | 30-32.5 | 32.5-34.5 | 34.5-37 | 37-39.5 | 39.5-42 | 42-46 |
| Arm length | 30 | 30.3 | 30.3 | 30.5 | 30.8 | 31 | 31.3 |
| Waist | 22-24 | 24-26 | 26-28 | 28-30.5 | 30.5-33 | 33-36 | 36-40 |
| Hips | 31-33 | 33-35.5 | 35.5-38 | 38-40 | 40-42.5 | 42.5-45 | 45-48.5 |
| XXS | XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|---|
| Bust | 70-76 | 76-82 | 82-88 | 88-94 | 94-100 | 100-107 | 107-116.5 |
| Arm length | 75.5-76.5 | 76.5-76.75 | 76.75-77 | 77-77.5 | 77.5-78.25 | 78.25-79 | 79-79.5 |
| Waist | 56-61 | 61-66 | 66-71 | 71-77 | 77-84 | 84-91 | 91-101 |
| Hips | 79-84 | 84-90 | 90-96 | 96-102 | 102-108 | 108-114 | 114-123 |
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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