KIDDY guardianfix 3 Instructions D'utilisation page 13

ENG
It is possible that the child car seat cannot be fastened as described, e.g.
when the belt buckle lies in the lap belt guides of the child car seat and
cannot, or cannot easily, be opened.
If the described situation occurs, the belt shortener (refer to point 3.1.1) or
the belt extender (refer to point 3.1.2) have to be used.
4. Removing of the child car seat
Unfasten the lap belt according to the instructions of your airline.
Do not forget to remove the belt shortener from the 2-point airplane belt.
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