Britax Willow Aspen User Manual page 60

WARNING!
Some vehicles have no seating positions which are compatible with
this child restraint. If in doubt, contact the vehicle manufacturer for
assistance. Forward-facing vehicle seats MUST be used with this child
restraint. Side-facing or rear-facing seats CANNOT be used. See the
diagram below.
This child seat can only be used in the following classes of vehicles:
multi-purpose passenger vehicles, passenger cars, or trucks.
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