Nylon 77%, Spandex 23%, lightweight, breathable & durable, sweat-absorbent, anti-slip. True graduated compression of 20 - 30 mmHg (CLASS II), with seamless woven construction, these fit snug with no loss of compression after long time wear.
Based on suggested measurements of the calf 11.5-14" XL and 14-16" XXL it was suggested to order up in size. I purchased two sizes and kept one, didn't return this one in time.