If you didn't get your flange to hook your converter to, call up ATR and they will gladly send you a replacement. I thought they didn't send mine, (I didn't see it with all the exitement ripping the box apart) So I called ATR and I was really suprised that after a month went by they remembered actually putting the cat converter flange in my box! Sure enough I double checked and it was wrapped up in the bubblewrap. Unfortunately I wanted to eliminate my converter so I had to order the other flange to hook directly to the exhaust pipes on the other side of the converter.($20)