Chevrolet 2008 Express Owner's Manual page 65

Driver Side shown, Passenger Side similar
If your vehicle is a cargo or passenger van with a
sliding door and it has a roof-rail airbag for the driver
and right front passenger position, the roof-rail airbags
are in the ceiling above the side window.
Driver Side shown, Passenger Side similar
If your vehicle has roof-rail airbags for the driver, right
front passenger, passengers behind the driver and right
front passenger, and the third row outboard passengers,
the roof-rail airbags are in the ceiling above the side
windows. On the driver's side of the vehicle, there is one
single roof-rail airbag for either vehicles with a hinged
door or a sliding door.
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