Abstract: A connecting system for providing a fluidic connection between containers, the connecting system having at least two connecting arrangements configured to produce the fluidic connection. Each container has an initial state in which the two containers are fluidically separated from one another and a connected state in which the two containers have been fluidically connected together by a relative movement of the containers. A securing device prevents relative movement of the containers in the initial state, and a receptacle is provided in which the securing device can be accommodated for enabling said relative movement. The system is usable in a method for preparing a mixture of substances in which the containers are placed in a connecting orientation with the securing device arranged between the containers in a manner preventing fluidic connection of the containers, and releasing the securing device for enabling fluidic connection the containers by a relative connecting movement.

Abstract: The fan housing for a multistage fan has a first housing part for receiving the electric motor, a second housing part mounted coaxially on the first housing part, and a housing cover mounted on the opposing side of the second housing part. So that fan noise is minimize during fan operation, for improved protection from external effects and to avoid tension originating from thermal expansion in the blower housing the housing cover for the second housing part has a peripheral cover edge portion and is pot-shaped or cap-shaped; the housing cover completely overlaps the second housing part; an overlapping peripheral portion of this housing cover has a radial spacing from the second housing part so as to form an air cushion between the second housing part and the housing cover and the cover edge portion of the housing cover is supported on the first housing part so as to enclose the second housing part.