In this owner's manual, explanation of child-restraint systems is provided for the following three types of popular childrestraint systems: infant seat, child seat, booster seat.
NOTE
Infant seat
An infant seat provides restraint by bracing the infant's head, neck and back against the seating surface.

Child seat
A child seat restrains a child's body using the harness.

Booster seat
A booster seat is a child restraint accessory designed to improve the fit of the seat belt system around the child's body.

Installing Child-Restraint SystemsMazda 6 Owners Manual: Head Restraints
Your vehicle is equipped with head restraints on all outboard seats and the rear
center seat. The head restraints are intended to help protect you and the passengers
from neck injury.
WARNING
Always drive with the head restraints installed when seats are being used
and make sure they are pro ...
Mazda 6 Owners Manual: Rear center seat belt removal/installation
Caution
The ELR has a spring that will unwind if the retractor's cover is
removed. The spring cannot be rewound by hand. If this occurs, the ELR will
not work properly. Therefore, do not disassemble the retractor.
4SD
1. Fold the rear seat back.
2. Remove the rear package trim.
3. Re ...