The first-ever Plantar Fasciitis compression sock that strengthens the foot structure and prevents Plantar Fasciitis symptom onset as well as overuse injuries. With precise targeted compression levels and cushioning, the FS4 Plantar Fasciitis sock features Compression Zone Technology® that is designed for proper foot support. Merino Wool or Ultra-Soft NylonMerino Wool - 100% recycled material, moisture-wicking, added warmth, durable, softUltra Soft Nylon -High quality, durable, moisture-wicking treatment with anti-odor treatmentTargeted ConditionsPlantar FasciitisFoot FatigueArch/Heel Pain Performance FeaturesMedical Grade SupportY-Gore heel for anatomical shapePatented Compression Zone Technology®Seamless ConstructionExtra cushioning without the bulkAnatomical left/right design for perfect fitAnti-bacterial fabric