Hi and thank you for the nice comments,
The sign was manufactured by "The Union Enamel Co Ltd Durban". This was an early enamel sign company in South Africa. I guess this sign was made in the 1930's given the style of the car in the picture and it has an "art deco" feel to it.
I forgot to mention in my previous post that the sign measures 800 x 1200 mm.
Here are some other Shell Oil signs in my collection. Will post more pictures on other subjects from my collection if you would like to see?
This one has more damage than the other but thankfully the important parts are not too bad. This sign measures 500 x 1020 mm.
Here's another - measures 970 x 970 mm, in great condition. Really heavy enamel!
Hope you like. Cheers.