Hopping on a Gyffy promotes balance and coordination in children while providing a fun workoutGyffy ships uninflated so parents can adjust the level of inflation according to the size and age of the child; package includes 1 valve and 1 plugInflated Gyffy measures 18" x 21" and 27" in diameter at the saddleMade from soft, super-strong, latex-free, BPA-free and phthalate-free vinyl for years of worry-free enjoymentSuitable for children 3 to 5 years of age