Designed by an orthopedic surgeon to help increase circulation in your hands and wrists by providing warmth and mild compression. Wear day or night to reduce pain, control swelling and promote healing. Breathable blend of 92% Cotton, 8% Spandex. Machine wash. Specify size: Measure length across knuckles. SM(up to 3 1/8"), MD(3 1/8"-3½"), LG(3½"-4"). If borderline, order down.