DESC: The Britax HIPPO Car Seat is the only car seat specifically designed for transporting children in Hip Spica Casts, Broomstick Casts and Ilfeld splints Every year thousands of infants & toddlers undergo surgery to correct hip and leg problems and must be casted for several weeks while recovering. These casts often make it difficult or impossible for children to use "regular" child car seats in compliance with State DMV laws. The HIPPO Car Seat is the ONLY chld restraint device designed specifically to accommodate most casts and ensure that these fragile children can be transported securely restrained and protected from additional trauma.