A housing for an airbag module for arranging on the steering wheel of a motor vehicle comprises a hinge mechanism for pivotably fixing the housing to a steering wheel and at least one fixing mechanism for additionally mounting the housing on the steering wheel in a floating manner. Specifically, the invention incorporates a double-belt press apparatus with a non-permeable upper belt, a highly permeable lower belt, a wedge type zone with adjustable spring compression, and a means for re-screening belt press filtrate with either a single belt press or multiple belt presses configured as a multi-step cascade of belt presses. The master directory comprises a taxonomy of categories.