They are made from durable and breathable materials like spandex and polyester. They keep your feet clean during bouncy jumping, warm in the cold, and fresh in the summer months. Due to the super grippy bottom of these socks, you are less likely to slide on trampoline parks, climbing areas, toddler areas, maze area, slick floors, tile floors, hardwood floors, etc. Machine Washable Specialized playground socks are socks specifically designed for playground use.