DetailsLasting Size Chart This merino wool t-shirt is suitable as a first layer year round for sports or casual activities. It is made of top quality sustainably sourced 16.5 micron merino wool. This is the finest wool available on the market, therefore it is extremely soft and itch free. This shirt keeps the skin dry, boasts outstanding thermal insulation and has moisture wicking properties. Flat seams and raglan sleeves create a comfortable fit.