1998 Buick Century Owner's Manual - Page 61

A rear-facing infant restraint(B) positions an infant to face the rearof the vehicle. Rear-facing infant restraints are designed for infants of up to about 20 lbs. (9 kg) and about one yearof age. This type of restraint faces the rear that the infant's head, neck so and body can have the support they need a crash. in Some infant seats come in two parts -- the base stays secured in the vehicle andthe seat part is removable. 1-53