At the top of level 6 are two columns " separated"
At the top of level 6 are two "columns" or posts that look like a ball would sit on it. They are a simple check valve is all.
I also thought it was for water restriction conservation until I read the invention patent. Pretty clever thinking. Not for water conservation at all. Basically its intentions are for when you are drawing a bath, excess water pressure doesn't send water up the pipe to the shower head by way of...