Description of Hot Chillys Micro-Elite Chamois Ankle Tights Moisture transport to keep skin dry and to promote warmth, Inherent anti-microbial properties to eliminate bacteria and odor, Lightly sanded face for comfort and performance. Features: Bi-component blend of MTF micro polyester Bio-Silver Antimicrobial polyester and Spandex Anatomical body fit design for freedom of movement and added support to help reduce fatigue Flat seam construction for seam strength and to eliminate abrasion UPF rating of 30+ Warmth Factor = 8