Kenney Adjustable Bracket, for 3/4" Curtain Rod, Satin Nickel, 2 Pack

What is length and width of the bracket base?

How long is the back piece?

i need to know what are the length these set will extend? 3.5 inch, and next one will go to 5.5 inch?anything between?

Why don’t center bracket come i have a kinney road it’s 5/8 in diameter. do you have the brackets to fit iwith it? does that mean i have to by 3 sets?