Kia Optima Hybrid 2017 Owner's Manual page 101

Safety features of your vehicle
Suitability of each seating position for "universal" category belted Child Restraint Systems according to ECE
regulations (Except Europe)
Use child safety seats that have been officially approved and are appropriate for your children. When using the child safety
seats, refer to the following table.
Mass Group
0: Up to 10 kg
(0-9 months)
0+: Up to 13 kg
(0 - 2 years)
I: 9 kg to 18 kg
(9 months - 4 years)
II & III: 15 kg to 36 kg
(4 - 12 years)
U = Suitable for "universal" category restraints approved for use in this mass group
UF = Suitable for forward-facing "universal" category restraints approved for use in this mass group (When you install the
child seat on Front Passenger seat, you should move the seat position to upward properly, to restrain child seat)
X = Seat position not suitable for children in this mass group
4-40
Seating Position
Front passenger Rear outboard
UF
UF
UF
UF
Rear centre
U U
U U
U U
U U