The SIXS Carbon Merino Underwear® long-sleeved stand-up collar shirt is breathable and thermoregulating in all weather conditions. The long sleeves completely envelop the arms, keep the skin fresh and lie between the skin and the underwear. At the same time, they easily protect against cold draughts when a short sleeve version is worn over the shirt. The contrasting stand-up collar also protects the neck from sudden changes in temperature and drafts. Features Seamless technology Antistatic system