Britax safe-n-sound BS0072E-i20133 Instructions For Installation & Use page 59

D. Engage seatbelt buckle & tongue. Push down on the
seat, whilst pulling the sash belt firmly. This should
make the lap belt tight across the restraint. Whilst
holding the seatbelt tension, ensure to remove all slack
from the lap part of the seatbelt (1) by pulling sash
belt (2).
E. The child restraint should now be firmly fitted to the
vehicle seat. Allow the excess sash belt to feed back
into retractor ensuring no slack has been created by
the belt path.
NOTE: Seatbelt extenders should not be used if the
seatbelt is long enough to secure the child restraint. If they
are used, the buckle must not enter the forward facing
belt path.
Always remove slack from seatbelt.
A loose seatbelt is dangerous.
H. If upper anchorage strap is folded up for storage undo
storage strap then lengthen. Fully press adjuster button
(1) while pulling upper anchorage strap (2) to lengthen.
I. Fit the attachment clip on the upper anchorage strap
to the anchor fitting as shown. Make sure to remove
as many twists as possible from the upper anchorage
strap.
Always attach the hook and remove slack
Push
down
2
1
Fully press Adjuster Button (1) while
pulling Upper Anchorage Strap (2) to
lengthen.
1
Attachment Clip
Attach
Car's Anchor Fitting
Instructions for Installation & Use
Pull to
remove
slack
2
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