Abstract: In a valve device in a connection piece, it is provided that the valve body is configured as a valve flap (20) with a closed surface, which valve flap is mounted in the connection piece via an elastic radial tongue (21) and rests against an annular supporting surface (26) in the closed position, and that the sliding member pivots the valve flap (20) in opening direction about the radial tongue (21) by pressure against its closed surface.

Abstract: The needle assembly consists of a plastic cannula (11) with a hollow hub (12) at its dital end, a steel needle (16) adapted for insertion into the plastic cannula (11) and having a ground tip (17) and a needle head (15) adapted for being detachably coupled with the hollow hub (12), and of a tube-like protecting cap for the elongated parts. According to the inventon the protecting cap (22) has a closed, thick-walled bottom (23) into which the ground tip (17) of the steel needle (16) is clampingly pierceable, thus providing a reliable connection between these two parts. The steel needle (16) can be thrown into the commonly used waste containers without the protecting cap (22) falling off.