CITROËN c4 picasso 2006 Owner's Manual page 135

C H I L D R E S T R A I N T S
Incorrect installation of a child seat in the vehicle compromises the protection of the child in the event of a collision.
III
The ISOFIX child seat recommended for your vehicle is the ISOFIX RÖMER Duo:
child seat.
feet do not touch the backrest of this front seat.
"
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