T-350 Part I.D.
In the picture below, what is this round disk called? The reason why I ask, I have been cleaning mine up and fixing the leaks. As I was scraping some gunk off the inside of this area, the whole thing move a little bit and allowed a tiny bit of fluid to start trickeling out. Theres no since in putting it back in if clearly it will leak from this area, but Im not sure what its called to get the right gasket/o-rings for it. Any help in the right direction is appreciated!