The Performance Trail looks different for a reason. The high cuff is a built-in scree-guard that helps keep out the trail while you're trail running. Below the cuff is a vented lower that increases breathability during highly aerobic activities. Similar to the Light Performance trail but designed in a medium weight for colder weather. Engineered for Whole Foot Comfort Knit with fine gauge merino wool for temperature regulation and ultimate softness. Wicks moisture, dries fast, and resists odors. Free Range Toe Box ensures room for your toes while contouring around them. Deep Heel Pocket wraps the foot, holds in place, and prevents blisters. Tapered Compression stimulates blood low and keeps the sock from falling down. Cushion zones in the heel, toe and arch.