The Ultra Probe interior in the episode Dragon's Domain contains many props seen in UFO, Doppelganger and other Gerry Anderson series. They were all originally made by Century 21 Film Props, led by Don Fagan.
Chris Bentley has catalogued many of the Century 21 props in his books, including Space: 1999 The Vault (2022), and in an article in FAB Annual 2023 published by the Fanderson fan club. Thanks to Chris for most of the research.
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Page copyright Martin Willey