New for Women
Shop NowFavorite icebreaker cut
"Love the neckline and cut of this top but definitely size up! So comfy, slightly stretchy, little more durable than some of the super lightweight fabrics."
799,00 kr
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799,00 kr
Good for:

83% Merino wool/ 12% polyamide/ 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: 60cm / 23". Amande is wearing size S.
Key product measurements:
Inseam Length:62.5cm (Based on size M)
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: 4.600644 / 5 from 621 reviews.
The 150 Siren Sweetheart is praised for its lightweight layers, perfect fit, and flattering appearance. Customers appreciate the softness and comfort, though opinions on the fabric vary. The high quality and versatile design make it a great addition to any wardrobe.
Review topics: ["fit","size","delivery","price","weight","quality","feel","problem","looks","material","top","shirt","layer","sleeves","fabric","colour","warmth","neck","wear","base layer","style","comfort","weather","neckline","winter","arms","stretch","icebreaker","medium","shape"].
"Love the neckline and cut of this top but definitely size up! So comfy, slightly stretchy, little more durable than some of the super lightweight fabrics."
— Melissa (5/5)
"Great base layer in charcoal. Grey is a little sheer but fine if you wear with a bra underneath. Hugs all the right places."
— Mark (5/5)
"Perfect for base layering under sweaters with low or wide necklines. No visible logo/brand name, which I prefer."
— Alaina M. (5/5)
"Superbe!"
— Lisette L. (5/5)
"You won't be disappointed it's fabulous to wear and washes so well. Im going to buy more as I keep going for this top to wear underneath clothing or its fabulous on its own."
— Kiwi (5/5)
"Had less than a year for an Icebreaker product and it developed a whole. Icebreaker customer service claims it's either wear and tear OR it's been miss-used. So will do nothing about the issue."
— Unhappy S. (1/5)
"Love it! Will buy it again"
— Gege (5/5)
"Great under anything from blouses to sweaters to provide extra warmth. Fits close so no extra bulk under clothes."
— Northeaster (5/5)
"The green Color is just perfect, and perfect fit. Thank you!"
— Montrealuser (5/5)
"To me, snow colour should mean white, this is definitely beige!"
— Stretch (2/5)
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 | XXL | |
|---|---|---|---|---|---|---|
| Waist | 24-26 | 26-28 | 28-30.5 | 30.5-33 | 33-36 | 36-40 |
| Hip | 33-35.5 | 35.5-38 | 38-40 | 40-42.5 | 42.5-45 | 45-48.5 |
| XS | S | M | L | XL | XXL | |
|---|---|---|---|---|---|---|
| Waist | 61-66 | 66-71 | 71-77 | 77-84 | 84-91 | 91-101 |
| Hip | 84-90 | 90-96 | 96-102 | 102-108 | 108-114 | 114-123 |
*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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