Take on long-distance and backpacking hikes with the Smartwool Mountaineer Classic Edition Maximum Cushion Crew Socks. These socks feature full plush cushioning for maximum comfort, while the elasticized arch brace provides a secure and lasting fit. The flat knit toe seam ensures in-shoe comfort. Made from wool, this is our thickest and warmest sock, perfect for keeping your feet comfortable during cold-weather hikes. Our first sock construction, only now featuring recycled nylon (content varies by style). This is our thickest, warmest sock. Features include an elasticized arch brace for secure fit and a flat knit toe seam for additional comfort. Weight: 0.348 lbs. Country of Manufacture: Italy. Material composition: 69% Wool, 30% Nylon, 1% Elastane. Sizing information: Small fits UK 2-4.5, Medium fits UK 5-7.5, Large fits UK 8-10.5, Extra Large fits UK 11-13.5.