Compression technologoy exert a gentle pressure reducing the diameter of distended veins and causing an increase in blood flow throughout the body. By compressing the surface veins arteries and muscles the circulating blood is forced through narrower circulatory channels. As a result the arterial pressure is increased which causes more blood to return to the heart and less blood to pool in the legs.Features. Designed and tested by tri-athletes that need one garment for three sport disciplines.. Pair 2 of calf sleeves.. Stimulates and improves circulation. Increases oxygen to the muscles. Reduces lactic acid. Brings relief from cramping. Improves performance. Assures fast recovery. Exclusive antibacterial fiber. Compression rate - 12-20 mmHg. Size - Large. Color - Red. Dimension - 7 x 4 x 1 in.. Item Weight - 0.3 lbs.