WARRIOR Quarter Zip Megaheat Long Sleeve Shirt Polyester 100% Polyester Generates heat by amplifying the wavelengths of infrared rays (daylight), Discharges sweat while keeping mositure from coming in, Creates heat from your sweat, Super lightweight - hollow fiber technology, Warrior mark on zipper Turn Inside Out, Machine Wash Cold, Wash with similar colors, Remove promptly after Wash, Only non-chlorine bleach when needed, Tumble Dry low, Cool Iron as needed, Do Not Dry Clean Vietnam