Russell Athletic Men's Coolcore Long Sleeve Compression Tee 84% polyester/16% elastane Xtreme compression cloth with Coolcore® technology. 92% polyester/8% elastane stretch mesh inserts with Coolcore® technology. Coolcore® is engineered to distribute moisture quickly throughout the garment. As the moisture spreads it will dry faster and keeps you cool and comfortable. 4-way stretch properties allow for increased mobility. Garment protects against the sun with 50+ UPF. Wicks moisture. Tagless label. Crew neck. Raglan sleeves.