Opel ASTRA K 2015 Owner's Manual page 87

Net pocket
Insert adapters into the required
position in the rails. The net pocket
can be suspended from the adapters.
Installation of hooks in the rails
Insert the hook in the desired position
first in the upper groove of the rail and
then press in the lower groove. To
remove, first pull out of the upper
groove.
Storage
Service box
Install two hooks in the upper rail.
Insert the upper brackets of the box
from above into the hooks.
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