The above brochure most likely dates from the late 1920s to mid‑1930s, and the evidence comes from the combination of manufacturers, corporate names, and the typography/graphic style used.

🕰️ Why the late‑1920s to mid‑1930s window fits

1. The companies listed only overlap under these exact names in that period

Several of the firms in the advertisement went through name changes or relocations that help narrow the date:

Hydrometer AG, Breslau 5

Hydrometer operated in Breslau (then Germany, now Wrocław) until 1945. The “Breslau 5” postal district format was used primarily between the mid‑1920s and late‑1930s.

H. Meinecke A.-G., Breslau‑Carlowitz

The Carlowitz district designation appears in trade directories in the 1920s–30s.

Siemens & Halske A.-G., Berlin‑Siemensstadt

Siemensstadt branding becomes common from 1920 onward, especially in industrial catalogues.

Bopp & Reuther GmbH, Mannheim‑Waldhof

The “Waldhof” designation appears in their catalogues from the 1920s onward.

This cluster of names and locations aligns strongly with the interwar period.

🎨 The graphic and typographic style

The design language of the brochure—heavy sans‑serif title, central technical engraving, and the clean, geometric layout—is characteristic of:

- German industrial advertising in the Weimar era

- Bauhaus‑influenced commercial graphics (1925–1933)

This style becomes less common after 1935, when more nationalistic design motifs dominate.

🏢 The distributor: Wassermesser‑Vertriebs‑Gesellschaft m.b.H., Berlin W15

The “W15” postal zone format was used in Berlin before the 1941 postal code reform, again pointing to a pre‑WWII date.

The company itself appears in German trade registers during the late 1920s and early 1930s, acting as a cooperative distributor for multiple meter manufacturers—exactly what the brochure shows.

📌 Most precise estimate

Putting all evidence together the estimated creation date is ➡️ 1928–1934 (most likely 1930–1932).

This is the period where all six manufacturers appear under these exact names, the postal districts match, and the design style aligns perfectly.