http://www.diyupholsterysupply.com/...tBy=&Category_Code=upholstery-spring

It is just an extension spring probably sold at most hardware stores. Just find the correct length and spring rate.... or buy on line in quantity. Springs with the same OD, length and wire diameter will have approximately the same spring rate as yours. Nothing too technical for those springs.

There are a couple of upholstery tips in the TIP SECTION/interiors


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