Abstract: Apparatus for determining and/or monitoring at least one physical or chemical process variable of a medium in a containment comprising at least one sensor element, at least one housing module and at least one flange, wherein the sensor element and the flange are connected with the housing module, wherein the flange in a first portion, which is at least partially media contacting, is manufactured at least partially of a first material, which is selected application specifically, and wherein the flange in a second portion, which is at least partially environment contacting, is manufactured at least partially of a synthetic material.