The Elmo is a skintight thermal long sleeve, crew neck, base layer that features Galvin Greens Skintight thermal technology. This has been specially designed to keep you warm even when the weather conditions are cold. The material, which is designed to keep you insulated, keeps the heat in but also allows moisture & any excess heat to be transferred away from the body where it evaporates. This gives total comfort & breathability. It is a must-have product especially when you need to keep warm.