Layer or wear the Icebreaker Tech 260 on its own for all-day comfort. The 100% Merino wool construction is excellent at thermoregulation while the heavier weight provides more warmth on colder days. It's suited for cool weather use that can extend to all seasons. Enjoy!
Performance Comparison

The Icebreaker Tech 260 is a great option for those with shorter arms and torso.
Photo: Amber King
Warmth
Featuring 260-g of 100% Merino wool, this is an exceptionally warm top that is also capable of offloading heat. The tightly woven fabric provides some wind-resistant when worn on its own, while the fabric does a great job wicking and keeping moisture away from the skin. The thicker fabrics add to its overall warmth, scoring it as a high performer in this metric. With a variety of weights available, it's a great option for wear in Polar temperature, layered appropriately in its own system.

Freezing our buns off on a negative 20-degree day, we test the capabilities of the super warm Icebreaker 260 in a layered system while running five miles through the pavement jungles of Mississauga, Ontario. Despite the frozen eye-lashes, we were still smiling!
Photo: Amber King
Breathability
Keeping with the pattern exemplified by 100% Merino wool base layers, the Icebreaker Tech 260 is quite breathable. When wearing it while ski touring, we experienced bouts of warm and cold temperatures, sweating while moving uphill and shivering on the way down. In both situations, this top kept us comfortable and dry - venting and breathing on the uphill while locking in warmth on the downhill. As a result, it offers a wide range of thermoregulation…it's capable of off-loading heat with the activity picks up, and can keep you warm with the temperatures plummet.
Comfort & Fit
Similar to other Merino wool products, the 100% Merino wool fibers are soft and comfortable against the skin. Featuring no-itch properties and a relaxed athletic fit, this shirt is a favorite among our testers. The size is true to fit, but unfortunately, it doesn't have much length. As a result, it rode up a little easier than other layers, but it didn't constrict through the shoulders or bust. While it's not as stretchy or tight as other base layers it did fit most of our testers. It can be worn all day and for multiple days on end.

This crew-cut base layer is soft and comfortable with a shorter fit then other Merino wool competitors tested.
Photo: Amber King
Layering Ability
Like all Merino wool shirts, the face fabric is a little grabbier than synthetics and doesn't slide as easily over other layers. We found that it grabbed tighter mid-layers, but performed just fine under jackets. It does accommodate a tank top or t-shirt for wear underneath during the warmer months.

Layer this with a mid layer and a comfortable jacket. While the sticky face fabric bunches more than synthetic competitors, it still functions well to layer under and over.
Photo: Amber King
Drying Speed
While this layer doesn't absorb a whole lot of water, its drying rate is a little lower than the rest. The top itself, surprisingly, doesn't absorb a lot of water which is not the pattern for most 100% merino wool tops. That said, with less water to evaporate during our drying tests, it still took 90 minutes to dry. As a result, the drying rate is a little lower than other tops. In the field, it seemed to do a great job wicking away moisture and didn't notice it lingering in the fabrics. Overall, despite its lower drying rate, we'd still recommend it for all conditions. Though if you seek a top that dries faster, take a look at a synthetic option instead.
Durability
Inherent to the properties of Merino wool, this is not the most durable base layer tested. The softer face fabrics can grab and snag trees or other sharp objects while hiking and the fibers will wear away faster when exposed to high-friction activities like off-width crack climbing or spelunking.

Aside from a little fabric pilling, this shirt is quite durable for a Merino Wool top.
Photo: Amber King
While it didn't show any significant signs of wear and tear during our testing period and is more than suitable for casual activities or wear around town, we noted a couple of stitching fly-aways and a little pilling of the face fabric. As a result, we would contest that when taken care of, this base layer will last you for a long time.
Best Applications
With its wide range of thermoregulation and comfort, it's a perfect option for all-day wear through all four seasons. We seriously think you could do anything in this top! Our only suggestion is to leave it at home if you plan on seriously exploring caves or canyons as the friction will most likely burn a hole through the fabric. We also wear a thinner top when the temperature gets warm.

Skinning, trail running, and hiking were all the different modes of testing for breathability in both a layered and unlayered system. Here the Icebreaker (that can't be seen) does well on this snowy day in the wet climates of Washington state.
Photo: Amber King
Value
This is one of the most expensive baselayers tested. While this Merino wool option stands out for its great craftsmanship and warmth, its performance isn't nearly as high as other cheaper options. As a result, it's not the best value and there are some better priced Merino wool contenders out there.
Conclusion
The
Icebreaker Tech 260 base layer stands out for its ample warmth and a wide range of thermoregulation. Pack or wear it on your next wild adventure into the wilderness this upcoming season.