The Merino Base T-Shirt is made of merino wool, elastane and polyamide; Polyamide fiber enhances wool's durability to provide long-term use; Elastane ensures flexibility to deliver unrestricted movement; Wool's natural properties enhance smell control and improve hygiene; Ideal for 35-50F temperatures and provides comfortable warmth; Modest green color offers camouflage and can easily match any color; The design is perfect for forest and marsh environments; Suitable for a wide range of outdoor activities including hunting; Can be perfectly paired with Merino Base Layer Pants; Provides superior comfort in cool and cold climates