The Downpipe-Kit fits in to the n20 engine:

BMW 125i F20 / F21
BMW 220i F22 / F23
BMW 228i F22 / F23
BMW 320i (x) F30 / F31 / F34
BMW 328i (x) F30 / F31 / F34
BMW 420i F32 / F33
BMW 428i (x) F32 / F33

Replacement for OEM BMW Part# 18327645666 from year of construction 10/2012+

High quality stainless steel 1.4301 (SS304)
CAD-Designed without main catalyst*
2 Lambda probe connections
100% perfect fit, replacing OEM
Less thermal load on the turbocharger
Significantly more torque and power from reduced back pressure
Connection diameter 105mm
Exhaust diameter 76mm

*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.