first filling state fig1 a 1 b and a second filling state fig1 c 1 d each in a side view fig1 a 1 c and a frontal view fig1 b 1 d a receptacle 2 for a head airbag 1 is implemented in a roof area of the vehicle behind an interior panel not shown in particular an upper area of a vehicle body side a lateral edge spar of the vehicle roof or the like is referred to as the roof area in the inactivated state the head airbag 1 is received folded in the receptacle 2 and concealed by the interior panel in case of a side impact or a rollover a controller not shown activates a gas generator 3 this gas generator generates a filling gas which flows through a gas inlet connection into a gas channel 1 1 of the head airbag 1 which is received still folded in the receptacle 2 at this point in time the gas channel 1 1 is implemented integrally with an airbag 1 2 which extends above the gas channel 1 1 when the head airbag 1 is completely filled fig1 c 1 d by corresponding hinges which may.