Get medical-grade support for your calves with the Zamst Adults' LC-1 Calf Compression Sleeves 2-Pack, which feature G-Fit technology that provides gradient compression from the ankle through the calf muscle to help encourage circulation and blood flow. Made of 93.6% nylon and 6.4% polyurethane for flexibility and comfort, the sleeves help flush out byproducts and lactic acid to reduce muscle vibration and fatigue for endurance and quick recovery. Elastic closures.