Below is information direct from Germany regarding this product.
It may show additional information about fitment and specification.
The WAGNERTUNING Downpipe Kit for Audi RS4 B5 / S4 B5 / A6 C5 2,7 Biturbo is designed as a high performance, direct factory replacement Downpipe Kit.
Engineered using the latest CAD design and flow technology, and constructed using top quality materials to our exacting standards,
the WAGNERTUNING RS4 Downpipe Kit provides maximum performance and longevity.
The RS4/S4/A6 2,7T Downpipe Kit features:
76 mm diameter tubing
SS304 stainless steel construction
eliminates power robbing pre catalytic converters
100cpi racing main catalytic converters
RS4 & RS6 turbo double flange
100% accurately fitting for the Audi RS4 B5 and A6 2.7 Biturbo with 230-250 hp (except A6 with automatic gearbox), adapts to the series exhaust system
with modifications towards the exhaust system also compatible for Audi S4 B5 ( except automatic gearbox)
Note:- These will require linkpipes fabricating to fit S4 and rear lambda cables extending (if fitted)