How to measure pirelli webbing for sofa i had to flip the clip over and bend the tab on an angle as the slots on mine are cut in frame at an angle. Pirelli webbing can be tacked or stapled directly onto a wooden frame. The webbing used on lower priced seating (and on some not-so-cheap budget leather sofas) is stretchable. This premium quality webbing can be used on settee's, chairs, stools etc. S. When Pirelli webbing reaches that state, it has no stretch and is useless. Elasbelt Webbing alternative to springs and replaces Pirelli Webbing. 91. For seats that have arms, you need to measure the width of the arm. Back-Tacking Strips Pirelli webbing is made of natural rubber and is the same webbing as used by Ercol and other high quality furniture. ugycndfcazttlfnabspakexelsddwnimovwbbihcgbghppgepptcyufuhuiignsdaatuauutilkwkfkvcqk