Initially single piece fastener for securing members having quadrilateral perforations

Abstract From the Canadian patent

A fastener for joining sheet material having aligned quadrilateral apertures includes a grommet and stud. The grommet has a head with spaced side portions and an opening therethrough. A pair of spreadable essentially parallel stems extend axially from the side portions on opposite sides of the opening and define a quadrilateral figure slidably receivable in the perforations. The stud is attached at one end integrally in a limited area to the grommet within the opening and arranged when severed from the head, at the limited area to move between the stem elements and to rotate thereby to spread the stem elements and lock the grommet in place within the aligned apertures. The extremities of …