Inflatable seat belts are now found in the back seats of some Ford & Lincoln vehicles (starting in 2011) as well as some Mercedes vehicles. The current Ford Motor Company (Ford & Lincoln vehicles) Inflatable seat belt system is approved for use with Doona car seat using a lap shoulder belt standard installation WITHOUT the base. With the base, the lock-off mechanism will not close around the inflatable seat belt. If the seat position has lower anchors, you can install your Doona base with the lower anchors. Please be aware that if you are installing the base with an inflatable seat belt, you will not be able to use the shoulder belt lock-off. Instead, lock off the seat belt with the retractor. When installing the Doona without the base, do not use the European method, use the lap-shoulder Belt standard installation.