Vauxhall Astra Owner's Manual page 78

Installation
There are two installation openings in
the roof frame: suspend and engage
rod of net at one side, compress rod
and suspend and engage at other
side.
Behind the rear seats
Adjust strap length on safety net by
attaching the upper hook to the eye of
the strap and attach to eyes in the
right and left of the floor.
Storage
Behind front seats
Adjust strap length on safety net by
attaching the upper hook to the eye of
the strap and attach to eyes in the
right and left of the floor.
Remove rear outer head restraints
and fold backrests forward.
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