Extensible window shading device

An extensible car window shading apparatus mountable inside the car and comprising a plurality of slats having at each longitudinal end a slat hole in which a slat spring attached to a slat stick is inserted, such that the slat stick extends outwardly from the slat hole, a plurality of panels, the plurality of panels numbering exactly twice the number of the plurality of slats, such that there is a panel at each longitudinal end of each slat, wherein each panel has a panel hole in which a panel spring is inserted, the panel hole being configured to receive the slat stick, and wherein the panels on each respective end of each slat are joined by hinges, such as to allow folding or deploying of the extensible car window shading apparatus by a user, and a support arm that keeps the extensible car window shading apparatus in folded position, wherein the support arm comprises an articulation that allows the user to temporarily push aside the portion of the support arm that keeps the extensible car window shading apparatus in folded position, such that the extensible car window shading apparatus can be deployed under the effect of gravity when the user needs the extensible car window shading apparatus in deployed position.