50 Roubles Heavy Tank KV-4

The KV-4 never reached production. Designed in 1941 as a proposed super-heavy tank exceeding 90 tonnes, it existed only as competing blueprints — over 20 separate design submissions were made by different Soviet engineers before the project was cancelled entirely. The German invasion that same year made the logistics of manufacturing such a machine a fantasy.

This coin belongs to the long-running Russian commemorative series honoring Second World War armored vehicles, many of which celebrate prototypes and experimental designs alongside fielded ones.