Not worth the money
"I have some older icebreaker thermal’s that are paper thin and work way better than the newer ones. Definitely don’t recommend for the price you’re paying"
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$260.00
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$260.00
A heavyweight merino wool base layer top designed to keep you warm and comfortable on the coldest of days, the 300 MerinoFine™ Polar Long Sleeve Half Zip features our premium, luxuriously soft ultra-fine merino fibres that are incredibly soft next to skin.
Good for:

100% Merino Wool. Exclusive of Decoration.
Machine wash cold gentle cycle. Wash with like colors. Do not use softener. Close all fasteners before washing. Do not bleach. Do not tumble dry. Dry flat in the shade. Cool iron. Do not dry clean.
Key product measurements
Back High Point Shoulder to Hem: 73cm/28.5in (Based on size M)
Fit
Slim
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Overall rating: 4.551724 / 5 from 29 reviews.
Review topics: ["fit","weight","quality","works","thickness","colour","buy","clothing","base layer","shirt"].
"I have some older icebreaker thermal’s that are paper thin and work way better than the newer ones. Definitely don’t recommend for the price you’re paying"
— Anonymous (2/5)
"Superfine soft and beautifully cut. I have a number of this brands expedition weight garments. They are fantastic. This top is so nice I’m hesitant to wear it for sport. It’s like a designer dress garment"
— Anonymous (5/5)
"This article runs a bit small so order up one size."
— Anonymous (3/5)
"My new favorite! Thick and cozy."
— Sean P. (5/5)
"Quality product, warm and perfect fit. Is great over a thermal and/or under a jacket so works well for layering also. So all-in-all, I am very happy with this purchase."
— Rocket (5/5)
"It is very comfortable and soft on the skin. Does exactly what it says on the tin - keeps you warm in very cold conditions."
— Mango (5/5)
"Good quality clothing, fast delivery, warm and cosy"
— Al (5/5)
"Good weight fabric and incredibly soft. Almost silk like feeling against the skin. Very comfortable and warm so far and looking forward to seeing how well it performs over time. Really impressed so far."
— D (5/5)
"I was really looking for a heavy base layer and purchased these top & bottoms immediately. The quality is still obvious. Warm, but still breathable, the Size medium is just a bit snug on my 6'0"" frame but still fine. I just completed a cold weather exercise the military where it was -15C to -23C. This is what I wore all weekend."
— Sarge (5/5)
"Use it for cold weather hiking and biking. It is warm and cozy. The zipper does not work properly as I need to twitch it left/right along the upper end to make it zip all the way. The zipper is anything but smooth as the other icebreaker items including a cardigan are, that i own. For a size large it needs to be longer to work optimal as an undershirt. The material is superb."
— Portalite (4/5)
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.
| XS | S | M | L | XL | XXL | XXXL | |
|---|---|---|---|---|---|---|---|
| Neck | 12-13 | 13-14 | 14-15 | 15-16 | 16-17 | 17-18 | 18-19 |
| Chest | 33-35 | 35-37 | 37-40 | 40-43 | 43-46.5 | 46.5-49.5 | 49.5-52 |
| Arm length | 33.5 | 33.5-34 | 34 | 34-34.5 | 34.5 | 34.5-35 | 35-35.5 |
| XS | S | M | L | XL | XXL | XXXL | |
|---|---|---|---|---|---|---|---|
| Neck | 32-34 | 34-36 | 36-38 | 38-41 | 41-43 | 43-46 | 46-49 |
| Chest | 84-89 | 89-94 | 94-102 | 102-110 | 110-118 | 118-126 | 126-134 |
|
Arm length |
85-85.5 | 85.5-86 | 86-86.5 | 86.5-87 | 87-88 | 88-89 | 89-90 |
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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