milestone Daybreak Long Sleeve Shirt

The day this shirt arrived, I took it straight up Mt. Hyonosen in Hyogo.

When you think about bringing a shirt to the mountains, the first idea is probably to use it in place of a wind shell. In fact most shirts from outdoor brands are nylon, using the same or similar fabric as a wind shell. They do behave much like a wind shell, plus you get the things only a shirt can do.

The Daybreak Long Sleeve Shirt uses a mesh-like polyester with vent holes on the surface. For wind resistance it clearly loses to nylon. But wind resistance and breathability are a trade-off, and for breathability this shirt clearly beats a nylon one. It also wicks moisture and dries fast. I sweated a fair amount and it dried surprisingly quickly.
Because it breathes so well, you can keep wearing it for longer even when it's hot, which is a real advantage for sun protection at altitude.

A shirt's other advantage is button adjustment. You get a wider range of ventilation than with a zipper: control airflow by how you button it, open the cuffs to let air in, and roll up the sleeves easily.

On the details, the Daybreak resists wrinkles and recovers well from them. It also has anti-static tape, so it's stress-free to wear.

As for the weak wind resistance, I have my own approach. You could throw a wind shell over it, but since the whole idea was to replace the wind shell with a shirt, that feels a bit clumsy.
Instead, pair it with active insulation, the exposed-fleece kind like Alpha Direct or Octa. Wear it on top when it's a little cold and wind resistance simply improves. When it's colder, put the active insulation underneath and the shirt on top and warmth jumps up. Colder still, and you're into rain-jacket territory. Active insulation is more compact and lighter than down, and used well it can approach the warmth of a thin down layer.

With the Daybreak Long Sleeve Shirt and a bit of layering, I feel I can now handle temperature ranges I couldn't before. And it works as everyday wear too. In this shirt you can even walk into a nice restaurant.