Kiddy Up crush resistant blue pit balls (1000ct). each ball measures 2.5 inches (6.35 cm) in diameter. Bright and colorful, great for ball pit fun. Kiddy Up pit balls are the perfect addition to any playroom, school, or backyard! these colorful pit balls are soft, but crush resistant to withstand all sorts of play. Kiddy Up pit balls were made with your child’s safety in mind. Fill up a ball pit and dive right into the fun!.