with a filter medium 46 that is comprised of a thin material it extends almost across the entire length of the support grid 40 only the area for attachment in the outlet socket 12 is spared an annular groove 45 with a seal ring 44 is provided at this location for sealing the outlet socket 12 a thread 47 only one turn is shown is provided for attachment the filter medium is glued on or welded on for example by ultrasound fig5 shows the detail v of fig3 at a larger scale this illustration shows that in the housing part 4 the tubular section 24 is formed in which the axial section 32 of the annular element 30 is provided that is a component of the lid 9 the annular element 30 forms the terminal disk 30 u2032 for the filter medium 27 that is connected to the terminal disk 30 u2032 by an adhesive layer 31 on the outer surface of the axial section 32 there are two annular beads 41 42 that rest against the inner wall of the tubular section 24 and in this way provide two axial seals at an axial spacing relative to one another at the end face of the housing part 4 a surface 34 is provided against which the collar 33 of the annular element.