Hot Chillys Men's MTF 4000 Crewneck Top 92% polyester 8% spandex Made in the USA and Imported Stretchy cotton feel with contrast stitching and antimicrobial treatment MTF Moisture Transfer Fabric to wick moisture away from the body OBP Oder Blocking Properties for a fresh base layer UPF 30+ for Ultra Violet Protection Factor to keep sensitive skin protected Medium Warmth Stretchy cotton feel with contrast stitching and antimicrobial treatment