Nike Youth Vapor Ultrafly 4 Keystone Shoes Perforated synthetic leather on the sleek, redesigned upper is breathable, durable and supportive. It’s also easy to clean after the game. The Nike Fastflex sole with 12-cleat configuration flexes to keep you ready for quick moves—infield or out. Rubber cleats deliver powerful traction as you round the bases. Soft and springy foam gives you quick-step comfort to last through practice and play. Mesh on the tongue helps keep your foot cool.