Men’s Tech Silk Longsleeve Crew is constructed using Polarmax's high-performance 100% Acclimate© Dry Polyester Eyelet Mesh. Lightweight, superior moisture management, incredible next-to-skin comfort and durable. Designed to fit regularly for a full range of motion with an unrestricted movement for hiking, walking, running, stretching and any other type of outdoor activity. This an ideal high-performance piece that can be a foundation of your cold-weather layering system or as a stand-alone shirt in the heat. With Acclimate© Dry moisture management system and Ag47© antimicrobial/anti-odor, you will stay dry, comfortable and odor-free during high-exertion activities in warm-to-cool weather. Construction features include Clean Seam© flat-seam technology to minimize irritation or chafing and self-fabric collar. Ideal for temps 40° - 60° F.