Seamless everyday base layers light top with long sleeves and a round neck with warm-touch inner layer. Breathable, soft-touch stretch fabric. One size. This garment has been tested to withstand temperatures from +12ºC (low activity) to -9ºC (moderate activity) during a standardised test with simulated wind of 0.4m/s wearing a jacket, trousers, underwear, socks, gloves and a knit hat.