I am looking for an upholstery supply, not sure of the name, can't seem to find it. It is a plastic U shaped strip with an edge to sew onto end of fabric, which is then snapped over the metal edge of the seat. Currently need a 7 or 8' strip of this. I could reuse the existing one, but as it is already been used, I question the strength of it, ie, tear on the dotted line...... (previously sewn area). I found one reference only, calling it a listing strip, and that reference suggesting reuse of existing one. Any ideas?