Features of Smartwool Women's Run Zero Cushion Low Ankle Sock 4 Degree elite Fit system for a dialled-in, Performance-oriented Fit Mesh zones for added breathability Shred Shield Technology reduces wear from toes Virtually seamless toe for enhanced comfort Women's specific Fit Height: Low ankle Zero cushion Fabric Details 51% Merino Wool 13% Nylon 32% Recycled Nylon 4% Elastane 51% Merino Wool 13% Nylon 32% Recycled Nylon 4% Elastane