100% Silk Imported What You Get: Terramar Sports Thermasilk Men's Shirt comes in Black, Natural and Grey options and in the following sizes: Small, Medium, Large X-Large and XX-Large. Made from 100% pure silk, they feel extremely smooth and keep you warm! These long sleeve t shirts are very light weight and do not have additional bulk and made with our ClimaSense treatment to neutralize odors, regulate your body temperature and wick away any sweat. Features: Ec2 Quick-Dri Thermoregulation Comfort Technology which allows the fabric to dry at a quick speed while regulating your body's natural temperature and keeping your body warm. It is built to stretch so there is no irritation or bunching. Terramar Sports is a United States based company making base layer gear for the most extreme outdoors person. Our products are created for every day adventures to difficult snowshoeing and mountain climbing. Keeping you warm is our job! How to Wash: In order to keep your Terramar Silk gear in perfect condition, we recommend washing these products in a washer and hang drying. As the material is very thin, hang drying will prevent any fabric from being pulled. Bleach only when needed.