Our Catalytic Converters are the same quality construction as OEM but at a third of the cost! These are a direct replacement for the original BMW catalytic converter. These bolt on to your stock exhaust manifold and muffler, no welding required. We offer cats for both pre-OBDII BMW's (pre 1996) and BMW's with OBDII (1996+). We offer both 50 state legal converters and less expensive 49 state versions. Meets all EPA and CARB requirements. A factory warranty is included: 5 year/25,000 for 49 State versions, and 5 years/50,000 miles on 50 State legal versions.