the attachment means a panel receiving opening 26 is formed in each member 15 and extends to the attachment through bore 25 whereby to permit the vertical end edge 13 of a panel member 12 to be slid into the attachment bore thus the panel member 12 extends out of the panel receiving opening 26 and the hinge is secured to the panel by merely sliding it over the vertical edge of the panel from the end thereof each hinge member 15 is also provided with an abutment surface 27 herein a concave surface extending parallel to the through bore 25 for abutment with a portion of the vertical edge 13 of the panel member 12 adjacent to the panel member to which the hinge member is connected to as shown in fig2 when the curtain panel members 12 are fully extended the end edges 13 are in abutment with the surface 27 in its fully extended position the panels 12 extend in an expanded accordion fashion with the panels traversing the central longitudinal axis of the curtain at an angle of approximately 10 u00b0 as shown the vertical end edges 13 of the panel members 12 are enlarged and hereinshown as being tubular edges having a hole 13 39 in at least the extremities of the ends of the tubular edge whereby to permit securement of the panels between a plurality of hinge members 15 the attachment through bore 25 in the hinge members 15 are also of circular cross section to receive the tubular edge of the panel members 12 it is within the ambit of the present invention to provide end edges 13 and attachment through bores 25 of cross sections different than circular as these provide a.