Atlas (under Sylvania Licence) 15W T12 Gold tubes

here are my 2 Atlas 15W (under Sylvania licence) 15W T12 Gold Tubes :)

these where a lucky ebay find recently and im very excited to get these as not only are they of the Rare 15W T12 size and coloured too which would of been an impressive find on their own

but there also quite historically important, notice the "Under Sylvania licence" this signifies that these tubes must of been some of the first made under Jules Thorns agreement with Sylvania to share lighting technology between the 2 companies

which you can read more about here

it would be interesting to know when these where made exactly but if I had to guess late 1940s to late 1950s