Opel ASTRA K 2015 Owner's Manual page 55

Seat height
Move switch upwards / downwards.
Seat inclination
Tilt front of switch upwards /
downwards.
Backrest inclination
Tilt switch forwards / backwards.
Seats, restraints
Lumbar support
Adjust lumbar support using the
four-way switch to suit personal
requirements.
Moving support up and down: push
switch up or down.
Increasing and decreasing support:
push switch forwards or backwards.
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