Our Stockings come in four levels of medically correct compression for better circulation and relief from achy legs. Mild Support - for tired achy legs, minor ankle, leg and foot swelling or mild varicose veins. Moderate Support - for travel, pregnancy, ankle, leg and foot swelling and more severe varicose veins. Firm Support - for post-surgical use, moderate edema or more serious leg swelling, and moderate to severe varicosities. Very Firm Support - Surgical Support must only be worn with your doctor's recommendation. Note: Firm and Very Firm Stockings should only be worn when recommended by a doctor.