Abstract: A strip of polymeric sheet material adapted to cut into lengths to form releasably engageable pieces of a fastener. The strip has a row of tab-like parts bent along bend lines out of the plane of a main part of the strip to define an opening through the strip; and the main part and tab-like parts of the strip have adjacent edge surfaces disposed at an included angle in the range of about 60 to 90 degrees with respect to the adjacent bend line so that when the tab-like parts on each of two lengths of the strip are simultaneously fully inserted through the openings in the other length with the tab-like parts projecting generally in opposite directions, the edge surfaces of the tab-like parts on one length will make frictional engagement with the edge surfaces of the main part of the strip on the other to frictionally hold the lengths in releasable engagement.