Focus Mk2 RS/ST Airtec Motorsport 3.5inch DownpipeAIRTEC Motorsport 3. 5 downpipe for Focus MK2 ST RS. The AIRTEC Motorsport 3. 5 downpipe reduces down to a 3 flange to fit the stock cat aftermarket de cat or sports cat. Can be easily cut and modified to fit a larger flange. Made to a high quality standard and all tubing is finished in brushed stainless steel. Designed and finished in the UK *This is a universal fitting product proven to give significant power gains as well as increased pops and