5 Mark Heidenheim an der Brenz

Heidenheim an der Brenz was home to significant optical and mechanical industries — Voith and Heidenheim's textile machinery firms kept the local economy moving even as the Imperial war economy strained municipal finances to breaking point. By 1918, coin hoarding was endemic across Württemberg, and dozens of smaller municipalities scrambled to issue their own Kleingeldersatz. Carl Edelmann, trading as W. Wellers Nachfolger, was a local commercial printer rather than a specialist banknote house, which shows in the relatively modest production values typical of late-war municipal issues.

The 145A.1d suffix in the DeNG reference suggests this is one of several recognized varieties within the type — likely differentiated by serial number range or minor typographic variation.