Ultimate Therapy Surgical Knee High Size Chart:

S M L XL 2XL 3XL
Ankle 6¼-7¼" 7½-9" 9¼-9" 11-12½" 12¾-15¼" 15½-17"
Calf 11-13½ 13-15½" 15-17½" 17-19½" 20-22½" 22½-25"
Length 14" & Over 14" & Over 14" & Over 14" & Over 14" & Over 14" & Over