by one of the barbs which bears against the corresponding face of piece 11 elasticity of the edge parts of piece 11 could be increased by providing a slit in the corresponding face of piece 11 through opening 16 in the embodiment of fig7 a spacing piece 11 39 which may have any suitable sectional shape such as circular or generally rectangular has a flexible elongate attachment 19 which extends from an edge of the face of piece 11 39 on which button 12 rests up to a pointed free end 20 a tapered conical opening 21 through the piece 11 39 extends from its face which contacts fabric 13 to its face which contacts button 12 adjacent the junction of attachment 19 in use the attachment 19 is passed through openings 12a and 12b of button 12 through the fabric 13 near one of the edges of piece 11 39 and then back through the fabric 13 directly into and through the opening 21 from which its pointed end 20 emerges via the opening 12a of the button the attachment is held in place by barbs not shown as described for fig6 or alternatively through a split or slotted part of the attachment 19 as for fig3 and 5 in any of the described.