What device is used to lock a lap and shoulder belt with an ELR retractor during car seat installation?

The locking clip is the correct device used to secure a lap and shoulder belt with an emergency locking retractor (ELR) during the installation of a car seat. This clip is essential for ensuring that the seat is tightly secured and does not move excessively during travel.

When using a lap and shoulder belt, an ELR will allow the belt to extend freely but will lock the belt in place only during a crash or upon sudden deceleration. In situations where there is a need for the car seat to be more securely anchored, a locking clip can be added to the belt system. By doing so, it prevents any slack from accumulating, thereby ensuring that the car seat remains stable and secure.

While other options such as safety latches, anchor straps, and adjustment levers are components that may be involved in car seat installation, they do not serve the specific function of locking the belt in place with an ELR retractor. The locking clip is uniquely designed for this purpose, making it a vital tool in child passenger safety.