I was supposed to get two (as it's x2 week) for the Vault Key built in my foundry and I only received one.
pixel_player65740469 Hi, the keys are not doubled during the double production week since they are designed to be limited and fixed. Other items will be doubled.
But when you look at them they don't have a 2x on them.
Here's the WIKI page regarding special weeks:
As above, It explains that the keys are NOT 2x.