The Downpipe-Kit fits to:

BMW 135i E82/E88
BMW 335(x)i E90/E91/E92/E93

made with high quality stainless steel 1.4301 (SS304)
100% perfect fit, replace OEM
less thermal load on the turbocharger
more power by reducing back pressure
significantly more torque
No Catalytic Converter*

*Off-road use only unless catalyst fitted in exhaust mid-section.
Removal of all catalytic converters will almost invariably make your vehicle illegal for use on a public road.
ECU will need to be coded to avoid engine management light errors.