Hi Does anyone know what type of aircraft this came off, i got it from a car scrapyard in 1977. Not much left of the instrument panel when i took it off, to help with id it has s.s.& s.ltd London mk x111D No1542/40. On the back it has ref No 6a/437.

colloquially known as a navigators altimeter!….used on wellys whitleys (with that date!), Stirlings etc