The item listed is a beautifully made pair of 200 Cell Sports Cats with a Euro style brushed finish. These 200 Cell Sports Cats replace the standard 400 Cell OEM cats, adding power and sound to the BMW M3 at a fraction of the price of BMW original catalytic converters. The cats are designed for you to place the original sensors or replacement sensors into easily. They are mandrel bent and TIG welded for the best possible quality of 304 grade stainless steel. The cats are 200 Cell, they will still pass MOT and emissions tests. Direct fit replacement, compatible with either OE, Chis-Tech centre section or any other centre section that fits OE cats.