catalyst

Hello good afternoon, I wanted to make a query I have a 1998 1.9 TDI 90CV and I am looking for a catalyst and my consultation is that they sell me one that is the same as mine but I do not know if the one that the engine has 11OCV has the model of mine is 3b and the other is 3bg please if someone can help me is urgent since I have to give it an answer thanks thank you

They sell universal Catalitics, the only thing that matters is the way for their installation, that is, oval or flat and more nothing does not matter, nothing more matters if you are going to weld the originals are wounded.