The men's Merino t-shirt can be worn as either a base, mid or even an outer layer, making it ideal for both winter and summer. This 170gm lightweight tshirt is made from 95% fine Australian Merino wool and retains its warmth even when wet. Merino wool acts as a thermo-regulator, keeping you cool in warmer climates and warm in colder climates. It's odour repellent, extremely breathable, silky smooth and non-itch.