SmartWool PhD Reversible Training Beanie - Past Season Double Layer Design with Clean Finish Seams - For Secure, Bulk-Free Fit. Lightest Weight Merino/Polyester Blend - Ensures Fabric Moves Moisture, Dries Quickly, and Maintains Shape in High-Sweat Activities. Jersey Knit with UPF 20 - Protection from harmful UV rays. Smartwool Logo On Front - Aesthetic styling. 56% Merino Wool, 44% Polyester