of the first set are spaced from one another at regular intervals the threads of the second set are spaced from one another at regular intervals in fig3 b a comparable embodiment as in fig3 a is illustrated in addition both the gasket layers 1 and 2 on their surface facing the central layer 3 are covered with an elastomeric fkm based coating 9 10 with a coating thickness of about 40 u03bcm this elastomeric coating seals interspaces which may exist in the sieve layer 3 in between individual threads 4 a to 4 c 5 advantageous coating thicknesses are between 20 u03bcm and 50 u03bcm it is preferred that both surfaces of gasket layers which face to the mesh layer be coated the sieve layer 3 itself is uncoated fig3 c shows a further embodiment of a metallic flat gasket according to the invention as a difference to the embodiment of fig3 a here the direction of the sealing beads is inverted they now do not point away from the sieve layer 3 but point towards the latter this arrangement of the beads also allows for a good sealing in the transversal direction thus in the plane of the layer and with respect to the permeation of a fluid from a passage openings 7 a 7 b to the passage openings 6 a 6 b 6 c fig4 in drawing 4 a shows a sectional view through.