Size Chart Exceptionally comfortable and versatile, these compression sleeves are clinically proven to improve performance, prevent injury, and reduce micro-trauma to the muscles in your lower leg. Stay energized on your next run with these calf sleeves. Features: - Encircles your muscles more than 300 times in graduated compression - Technical performance knit delivers exceptional air flow - Halo top-band keeps calf sleeves in place below the knee - Supremely smooth yet durable - 79% Polyamide (Nylon), 21% Elastane - 20-30 mmHg graduated compression - Low-maintenance ownership - machine wash and dry