Collectors confirm that the logo engraving was originally factory-filled in white or gold, so a restoration corresponds to the original state. Outpatient refilling is generally carried out via boutiques or specialised engravers, similar to name engravings. As a DIY solution the white 'Neocolor II Wax Oil' pencil by Caran d'Ache is recommended, also suitable for gold fills. The original originality is not impaired by it; decisive is clean execution.