A locking clip must be used on safety belts that have:

  1. a continuous loop lap-shoulder combination safety belt AND
  2. a sliding latch plate (the portion that snaps into the buckle) AND
  3. a retraction system that only locks when slamming on the brakes or in a crash.

Do not use a locking clip on a lap-only safety belt. A special belt-shortening locking clip should be used, but very few vehicles require this. Check the manual of your car!

Courtesy of Albany County Department of Public Works, Traffic Safety Education Programs