1.   For older cars you might need a locking clip.

2.   If your belts cannot be switched to automatic, the locking clip must be used to take up the slack in the safety belts.

3.   Locking clips can keep the belts from loosening.

4.   Seat belts that lock only in emergencies need a locking clip to hold car seats appropriately.

5.   Some seats require locking clips to keep retracting shoulder harnesses tight.