STRASSBURG SOCK LARGE The Rapid Rise Of Alex Michelsen ATP Tour Tennis. PRODUCT DETAILS: Medically proven soft night splint For Plantar Fasciitis, medical research shows average recovery time of 18. 5 days with 97. 8% recovering within 8 weeks. Also effective for Achilles Tendonitis and Tight Calves Recommended by top podiatrists, physical therapists, orthopedic surgeons, athletics, and top sports medicine docs. Measure Calf at it largest point, just below knee The Strassburg Sock REGULAR SIZE (Fits calf size up to 16 inches) (Measure AROUND calf at the widest point.) The Strassburg Sock LARGE SIZE (Fits calf size 16 to 21 inches) (Measure AROUND calf at the widest point.)