Weber carb setup question

Hi people, I'm just about to service my carb and was wondering what the deal with the 7mm insulator base gasket? How come you don't get one in the kit if you buy one new and it's not on the weber fitting instructions either! I have one on my car at the min but don't even know if I need it? Especially as I bought a service kit and I got a thin cardboard base gasket, which one do I use?

Thanks for any help

if it didnt have one originally then you dont need it

Well I can't remember if it was originally fitted or came with the newer carb when I bought that! I've had up 2 different weber kit diagrams for the same kit, the older looking diagram just has a gasket and ther newer looking diagram had the insulator block! Both diagrams had the same kit number at the top of the page so was completely confusing

the one I got didnt have one anyway, and there isnt one in the weber.pdf manual in my sig either so no need