Choose this converter for its brand name. Together with the new lambda probe, it passed the CA smog test for the first time. Before this test, the smog failed twice. The inlet is wide open and the pipe welded to the port flange was angled so that the o-ring appeared to hit the pipe and prevent a good seal. I cut off the intake pipe to prevent leaks and used paste to seal the exhaust pipes. The socket was a perfect fit. No leaks. The cat could use some improvement by positioning the intake pipe farther from the flange with 3 holes to use the o-ring and also with a heat shield the cat is bare on the outside. 4 stars for lack of perfection.