Britax Safe-n-sound BS8100A-020133 Series Instructions For Installation & Use page 15

Shoulder height markers B and
C are visible with the headrest
in the upper positions.
YOUNGTODDLER
Shoulders must not be below the lowest marker.
Use the in-built harness.
From approximately 6 months of age.
However, Britax recommends that you keep your
child in a rearward facing restraint for as long as
possible (up to approx 12 months).
Marker A
SHOULDERHEIGHTMARKERS
ANDAGROWINGCHILD
Marker C
Marker B
Marker A
Instructions for Installation & Use - Series No. BS8100A-020133
OLDERTODDLER
When shoulders are in-line with middle marker,
Change to Booster Seat mode.
To approximately 4 years of age.
Marker B
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