Abstract: A hydraulic unit for a motor vehicle brake system operating on the recirculation principle, in which each brake circuit has in the region of the hydraulic unit a prefilling location which opens into the pump suction conduit between the pressure-retaining valve and the change-over valve for the purpose of receiving brake fluid. The hydraulic unit can thereby be prefilled with lower complexity and cost in terms of time and processes prior to installation in the vehicle.

Abstract: A pneumatic brake booster includes a booster housing, subdivided into at least two chambers by at least one axially movable wall to which a pneumatic differential pressure can be applied, a control valve controlling the differential pressure and being arranged in a control housing, an operable input member, connected to a valve piston, an output member which applies a boosting force to a master cylinder, as well as an accommodating element, which accommodates a rubber-elastic reaction element and the output member abutting thereon in a radial direction, with the accommodating element being axially and radially supported on the control housing and being held in an axial direction by means of a holding element.