Pretty sure that's the pressure bypass spring, ball and cup from the
oil filter adapter. It's function is to bypass the filter if the pressure inside it gets too high from the filter being clogged so at least you get
oil to the engine even if the filter is clogged.
I replaced two of them and finally went to an external adapter without the bypass. The problem is in the way they seat the retaining cup. It's just a press fit and can pop out without a lot of trouble. Changing the filter won't do any good since the problem is in the adapter.
DonC