Britax Safe-n-sound BS8100A-020133 Series Instructions For Installation & Use page 27

ADJUSTINGEASYADJUST™HEADRESTANDHARNESSSTRAPHEIGHT
A. You do not need to remove the restraint from the vehicle to
adjust the harness or headrest positions.
Small adjustments maybe done with the child in the seat.
The child will need to lean forward to allow the headrest to
be adjusted.
To adjust the headrest; lengthen the harness, lift the
Easy Adjust Headrest Lever at the top of the headrest,
raise/ lower so that the shoulder strap slots are level with or
slightly above your child's shoulders. If the headrest is just
above the shoulders then the harness level will be correct.
B. To lengthen harness press harness adjustment button or lift
lever while pulling on both shoulder straps evenly until the
harness will accommodate the child.
Instructions for Installation & Use - Series No. BS8100A-020133
HOWTOUSE
Pull to
lengthen
Press and
hold or lift
lever
Easy Adjust
Headrest lever
B
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