an automobile seat includes a head rest for use by an adult which can be converted to an infant seat by pivoting a portion of the back rest forwardly and extending the infant or child seat from a storage compartment , and lowering the head rest which can be locked or secured to the child seat to serve as a restraint for the child . the child seat , which is pivotally mounted between its retracted and extended positions , is locked in each of said positions to provide security and reliability in both modes of operation or use .