MODERN COMFORT. RETRO STYLE. A perennial favorite, the Nike Air Max 90 Leather Boys' Shoe (3.5y-7y) delivers plush, flexible cushioning and durable support in an iconic design that's set the standard for over 25 years. Max Air unit in the heel offers lightweight impact cushioning. Full-grain leather overlays provide durable support. Soft, cushioned collar provides a contoured fit. Grade school size range: 3.5y-7y "