Its shell fabric, labeled “Diolen Cotton,” evidences a blend likely in the range of 65% polyester to 35% cotton—common among performance fabrics between the 1960s and 1980s. The shell presents characteristics in line with other regional outerwear of the era, structurally reminiscent of US M-65 twill shells or the cotton-based yet functionally-driven Ventile cloths from the UK, despite the latter’s absence of synthetic fibers.