The invention relates to a container closure system containing an overpouch with an intransparent first foil (10) and a transparent second foil (20), a transparent primary container (2) for holding a transparent pharmaceutical solution (3), wherein the transparent primary container (2) is packed within the overpouch (1) and labeled with at least one label (4) and wherein the at least one label (4) acts as a light absorbing segment having a reflection R L for light in the range of 350 nm to 800 nm and an inner surface (18) of the intransparent first foil (10) of the overpouch (1) acts as a light reflecting background having a reflection R F for light in the direction of the primary container (2) in the range of 350 nm to 800 nm with R F >； R L . By the transparent second foil (20) and the inventive reflection properties it is achieved that the at least one label (4) on the primary container (2) is visible and readable. Additionally, visual inspection of the content of the transparent primary container (2) is possible. A good contrast is achieved to enhance machine and human readability.
