A modular wall sleeve comprising a mounting plate an air outlet screen at least partially covering an air passage opening of the mounting plate, and a front panel at least partially covering a front side of the mounting plate, wherein the mounting plate comprises a front panel receptacle, wherein the front panel is detachably attached to the front panel receptacle, wherein the front panel receptacle and the front panel comprise complementary fastening means which are releasably engaged with one another, wherein the mounting plate comprises the front side, a rear side and the air passage opening connecting the front side and the rear side, wherein at least one air outlet pipe receptacle is located on the rear side of the mounting plate, which at least one air outlet pipe receptacle is arranged in such a way that an air outlet pipe on the wall side can be detachably attached to the mounting plate by means of the air outlet pipe receptacle, characterised in that the wall sleeve comprises an adapter for connecting the air passage opening of the mounting plate to a wall-side air outlet pipe or a wall opening, wherein the air outlet pipe receptacle is an adapter receptacle, wherein the adapter is detachably attached to the adapter receptacle, wherein the adapter receptacle and the adapter comprise complementary fastening means which are releasably engaged with one another, the front side of the mounting plate comprises at least one air outlet screen receptacle, wherein the air outlet screen is releasably attached to the mounting plate by means of the air outlet screen receptacle, wherein the air outlet screen receptacle and the air outlet screen comprise complementary fastening means which are releasably engaged with one another. a mounting plate an air outlet screen at least partially covering an air passage opening of the mounting plate, and a front panel at least partially covering a front side of the mounting plate, wherein the mounting plate comprises a front panel receptacle, wherein the front panel is detachably attached to the front panel receptacle, wherein the front panel receptacle and the front panel comprise complementary fastening means which are releasably engaged with one another, wherein the mounting plate comprises the front side, a rear side and the air passage opening connecting the front side and the rear side, wherein at least one air outlet pipe receptacle is located on the rear side of the mounting plate, which at least one air outlet pipe receptacle is arranged in such a way that an air outlet pipe on the wall side can be detachably attached to the mounting plate by means of the air outlet pipe receptacle, characterised in that the wall sleeve comprises an adapter for connecting the air passage opening of the mounting plate to a wall-side air outlet pipe or a wall opening, wherein the air outlet pipe receptacle is an adapter receptacle, wherein the adapter is detachably attached to the adapter receptacle, wherein the adapter receptacle and the adapter comprise complementary fastening means which are releasably engaged with one another, the front side of the mounting plate comprises at least one air outlet screen receptacle, wherein the air outlet screen is releasably attached to the mounting plate by means of the air outlet screen receptacle, wherein the air outlet screen receptacle and the air outlet screen comprise complementary fastening means which are releasably engaged with one another.