When I put motor oil in my 02 kj ,what's the plastic piece?

[discogypsy]

I put engine/motor oil in my 02 kj liberty for my 1st time and noticed a piece of plastic, kinda long,has a flat top with a lil handle, that I removed b4 putting the oil in.. It was cracking and I need to replace but wtf is it?
Thanks for taking the time to answer if u do

 

[DadOSix]

Mopar Parts Oil Fill Baffle 53032126AA

https://parts.mopargenuineparts.com/oem-parts/mopar-baffle-cap-oil-fill-housing-53032126aa?srsltid=AfmBOork4Aw8CZFQRexfwHwJuOqp4_UtVKySJqFZpu3a4OLyEqx-g-ap

And -
Thread '2004 Liberty Sludge in Oil fill neck'
https://www.jeepkj.com/threads/2004-liberty-sludge-in-oil-fill-neck.57658/

 

[discogypsy]

Thanks for your accurate reply! It's the baffle cap oil fill housing,I just ordered a new 1 by following your link.