Madeira Fire Fighter No.40 Flame Resistant Embroidery Thread (Cop) (Navy (1643)) Madeiras Fire Fighter No.40 is a flame and heat resistant embroidery thread which is ideal for the production of motor sport clothing, workwear and protective clothing. Fire Fighter is also used to embroider seat cushions of aeroplanes and wherever special safety considerations are essential. Fire Fighter is made from 100% Aramid and contains Nomex branded fibers from Du Pont. Complies with ISO standards ISO-6941/ISO 15025. Available in 25g Cops.