If a vehicle belt is equipped with a switchable locking retractor, the belt should be switched to the ALR mode when installing Liing baseless.
If your vehicle belt is not equipped with an ALR switchable retractor, the lap belt must stay tightly adjusted around the Carrier when you check for secure installation. In some vehicles the latchplate of the vehicle belt may act as the mechanism that keeps the lap portion of the belt tight. If it does not stay tightly secured around the Carrier, then a locking clip may be used to obtain a secure installation.
Locking clips are available for purchase through Customer Support at email@example.com or 1-866-656-2462.