This combo comprises of two pair of socks: T1 endurance and Checkmate endurance socks. Our breathable cotton, medical-grade compression socks (20-30 mmhg) eliminate muscle fatigue, swelling and cramping from long rides. These socks have gradually reduced compression, so the compression is tightest at the ankle, ensuring optimal blood flow back to the heart. Checkmate- T1 Combo Compression Socks