Fastener

Claim 1

A fastener for attaching an element to a planar body having first and second opposing surfaces and an aperture extending between said surfaces, said fastener comprising: a base to which said element is adapted to be attached, said base having a peripheral surface; a resilient non-return piece extending from a first surface of said base, said non-return piece including a stem secured to a central portion of said base surface and extending in a first direction essentially normal to said base surface, laterally extending connecting elements fixed to said stem, and thin connecting pieces connecting said laterally extending connecting elements to said base, said non-return piece being shaped to fit through said aperture whereby said connecting elements engage said first surface of said planar body; and at least two fixing elements mounted on said base, each of said fixing elements being symmetrical about a vertical plane passing through said stem and comprising an arm adjacent to, and extending parallel to, said peripheral surface of said base, each said arm slanting away from said first base surface in said first direction, whereby said arm defines a distal end spaced from said first base surface in said first direction, each of said fixing elements also comprising a resilient support element extending from said distal end and having a planar surface facing and engaging said second body surface when said non-return piece is inserted in said aperture with said connecting elements engaging said first surface, wherein said fixing elements do not extend beyond said base peripheral surface in any direction transverse to said first direction.