transparent outside and opaque inside I have an element in my model, which is, when exported e.g. to DAE or obj, turns "inside out"

However, within blender itself this element is rendered absolutely ok, both Eevee and Cycles:



What am i doing wrong?
It must be a problem of flipped normals, some softwares only display the normal side of the face. select your object and in Edit mode press ShiftN.