Hey I got a question....what are the bumpstops? Is it the yellowish foamy-rubbery thing? Or is the black rubber thing above that?

I have been trying to install my springs and not sure which thing to cut---they say cut the bumpstop in half..but I dont even know what it is..lol.
Thanks for the help guys

I think I may have made a big mistake, I cut the black rubber thing that looks like the bumpstop...not the yellow. Luckily I still have the pieces to put it back on my new strut. You think this will affect my ride quality or suspension system.
Mike