Won't fit

So I bought these for my 4G or 5mm lobes and I'm not sure how to put them in. They don't seem to be screws. Do I just somehow push them in until the get into the middle part. I tried but it was not going through

So I bought these for my 4G or 5mm lobes and I'm not sure how to put them in. They don't seem to be screws. Do I just somehow push them in until the get into the middle part. I tried but it was not going through