The Nike Shox R4 Men's Shoe offers the ultimate in responsive cushioning with four columns of support under the heel. Its lightweight, synthetic upper is soft and durable, and perforations near the toes and around the ankle enhance breathability. Synthetic leather upper for durability. Lightweight Phylon midsole cushions the forefoot. Air-Sole unit under the forefoot offers flexible cushioning. Rubber waffle outsole provides great traction.