I have this flange extender and as you can see it comes with for screws that probably can be used when there is wood floor (main or upper level floor). I am installing this in the basement and the floor is concrete slab. Since I am tiling I will need to install this. How do I use the four screws in this situation or what do I use to functionally replace them
The existing flange is metal in my case
The existing flange is metal in my case