SKU# 14437 | MPN: M2-SUB01-FP25UBig mouth with 3″ piping ending in 2.5″ flange to fit OEM or M2 lower part. no lambda fitting.Suitable for; 2001 – 2005 Impreza WRX and WRX STI Version 7/8/9, 2.0L Saloon and Wagons. Will NOT fit Version 10 or later models.