Use Child Restraint System that have been officially approved and are appropriate for your children. When using the Child Restraint System, refer to the following table.

U = Suitable for "universal" category Child Restraint Systems approved for use
in this mass group
U* = Suitable for "universal" category Child Restraint Systems with seat height
adjusted to the highest and rearmost position
UF = Suitable for forward facing "universal" category restraints approved for use
in this mass group
L = Suitable for particular child restraints given on attached list. These restraints
may be of the "specific vehicle", "restricted" or "semi-universal" categories.
B = Built-in restraint approved for this mass group.
X = Seat position not suitable for children in this mass group.
❈ Never install a Child Restraint System with a support leg on the front passenger
seat and the second row center seat.
Securing a Child Restraint System with a lap/shoulder belt
i-Size Child Restraint Systems according to ECE regulationsKia Niro 2017 (DE HEV) Service Manual: Front Door Belt Inside Weatherstrip Repair procedures
Replacement
1.
Remove the front door trim.
(Refer to Front Door - "Front Door Trim")
2.
Remove the front door belt inside weatherstrip (A).
3.
Install in the reverse order of removal.
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Kia Niro 2017 (DE HEV) Service Manual: Front Seat Belt Retractor Components and components location
Component Location
1. Front seat belt retractor
...