Part 09-903-0. The Vox standard tremolo was fitted to several early/mid 1960s solid-body Vox models with un-radiused fingerboards: the Dominator, Apache, and later versions of the Shadow, and Duotone. Note these are all UK-produced (JMI) models. Later Italian-built guitars, and British guitars with a curved fretboard did not use this part. British built Vox's with a curved fretboard used the de luxe tremolo.
A major advantage of this design was the fact it required no body routing - unlike the de luxe tremolo - allowing Vox to use one body for numerous guitars (Stroller, Clubman, Duotone and Shadow).
The unit was a combined bridge/tremolo/tailpiece - and as such had no adjustable saddles, making height and intonation adjustments impossible, although perfectly adequate as a tremolo. The unit was made up of numerous parts, the majority chrome-plated. The main body of the tailpiece is etched VOX PAT. APP. FOR., although a search of patent archives doesn't seem to include this part (if you know better, please comment. Perhaps it was never granted? There were a LOT of similar vibrato/tremolo unit designs being patented in the early/mid 1960s. This part was most likely produced for Vox in Torrington, Devon, UK. The two 'end caps' for the string bar are marked 'Made in England Torrington' and B-65 and M-651 respectively - look at the images below.
List of Vox guitar tremolos