I do not know what you mean, but this pad is in excellent condition, nothing is missing.
Since I'm not home i took a picture I had from my unboxing of my NOS CD32, as you can see in the marked area the CD32 pads came with a rubber Dpad with adhesive on that is ment to stick on the dpad area on the controller.
Those tiny dents on the controller is not ment to be used as is, they are ment to hold the rubberpart from slipping of since the adhesive rubber part has indentions on the back to fit perfectly.
Seems many people are missing this part tho.
I can take better pictures showing it on when I get home if you like.
But this is one big reason why you see so much rant on the CD32 controller since people don't know that the dpad ain't supposed to just have those tiny dents on it but a propper dpad with directional cross.
Edit: Should make a mold and make new ones for those who are missing em