1997 Buick Century Owner's Manual - Page 66

5. Pull the rest of the shoulder belt all the way out of the retractor to set the lock. 6. To tighten the belt, feed the shoulder belt back into the retractor while you push down on the child restraint. 7. Push and pull the child restraint in different directions to be sure it is secure. To remove the child restraint, just unbuckle the vehicle's safety belt and let it go back all the way. The safety belt will move freely again and be ready to work for an adult or larger child passenger.