Children should ride rear facing as long as possible. Rear-facing only car seats often are rated for use from 30 pounds (or 30 inches) to 35 pounds (or 32 inches). Convertible seats can be used rear-facing up to 35 to 50 pounds depending on the seat. The longer a child rides rear-facing, the safer they are. Children under 2 years of age are 75% safer riding rear-facing then forward-facing