<p>The latching device (16) has an elongated latching hook (19) with a latching projection (20). A latching opening (30) for outwardly bounding snap tab (31) is formed in the housing portion (14), and the latching projection is provided on latching opening. One introduction bar (36) with an insertion bevel (37) for the latching hook is arranged in the underside of latching opening. Two latching tabs (40) are engaged into latching opening and provided with a free tab end projected into the path of latching hook when inserted into the latching opening. An independent claim is included for pump.</p>
