Features of the Smartwool Men's Merino Sport 150 Boxer Brief Fabric combines the moisture management, temperature regulation, and odor resistance of Merino with the durability and quick dry time of polyester Double front panel designed to provide extra support Wide elastic waistband (40mm) designed for maximum comfort; 100% Merino next to skin Flatlock seam construction designed to minimize chafing Fabric Details Body: 56% Merino Wool, 44% Polyester Back Panel: 54% Merino Wool, 46% Polyester