Performance Stretch Lightweight Hoodie with Solar-Factor UPF 50+ UV Protection keeps you cool and dry with moisture-wicking and sweat-powered cooling technology. The Lightweight Open-Air Mesh Fabric is breathable and quick-drying. Performance Stretch Lightweight Open Air Mesh Fabric Solar-Factor UPF50+ Technology Moisture Wicking Technology Sweat-Powered Cooling Quick Dry and Breathable Zippered Chest Pocket Hidden Thumb Hole on Cuff Soft Seaming for Comfort Against Skin Specs 98% Polyester; 12% Spandex Machine wash cold with like colors, Only non-chlorine bleach when needed, Tumble dry low, Remove promptly, Cool iron if needed Fit The model 5'10" and 200lbs is he is wearing a size large Relaxed fit for extra comfort and mobility, if you think you are between sizes best to buy the smaller size.