An airbag module having a first shell (10) forming a first gas chamber (GI), a first inflator for the first gas chamber (GI), an adaptive influencing device for influencing the ventilation or shape of the first gas chamber (GI), and an actuation unit (40) for the influencing device. The actuation device (40) has a second shell (44) forming a second gas chamber (G2), and a gas source. The state of the influencing device changing upon actuating the gas source. A tensioning element having a first end (62) is coupled to the adaptive influencing device or forms the device, and a second end (64) is coupled to the second shell (44) when the second gas chamber (G2) is not filled and is decoupled from the second shell (44) when the second gas chamber (G2) is filled.