The therafirm compression stockings 20-30mmhg is designed to improve circulation relieve tired heavy aching legs and prevent moderate swelling. the compression stocking features true gradient compression delivers a controlled amount of pressure greatest at the ankle and gradually decreases towards the top of the stocking to promote better blood flow. the soft comfort band of the compression stocking is non-restrictive while staying in place for all day wear.  this style is knee high.   be sure to use the size chart and measuring instructions to determine best size and fit.   size guide   size ankle calf length small 15.9cm - 18.4cm 26.7cm - 33cm 27.9cm - 38.1cm medium 19.1cm - 22.9cm 29.2cm - 35.6cm 30.5cm - 43.2cm large 22.9cm - 25.4cm 31.8cm - 38.1cm 33cm - 45.7cm x-large 25.4cm - 28.57cm 34.3cm - 40.6cm 35.6cm - 48.3cm xx-large 28.57cm - 31.8cm 36.8cm - 43.2cm 40.6cm - 53.3cm xxx-large 31.8cm - 34.92cm 41.9cm - 52.1cm 40.6cm - 53.3cm xxxx-large 34.92cm - 38.1cm 50.8cm - 61cm 40.6cm - 53.3cm "