Abstract: A cover of a means for holding children and/or babies, the holding means having at least one opening, wherein the cover includes: (a) means for releasable fastening to the holding means, wherein attachment of the cover to the holding means enables the cover to match its form to openings of the holding means, (b) a layer configured to at least partially filter air introduced via the openings into the holding means, the layer including at least one layer including non-woven material, and (c) at least one window, whereby the child in the holding means is capable of viewing outside the holding means. The windows include a layer impermeable to at least one of the group including dust, air pollutants, viruses, (Rubber) bacteria, UV radiation, liquids and insects.