When running a larger intake system, such as our own, routing the factory coolant hose under the system may not be possible on some vehicles, or may fit snugly on others. We've redesigned the hose as a plug and play upgrade that neatly runs under the intake for a clean install with minimal stress on the part. Fits Audi A3 15-19, A3 Quattro 15-20, Q3 19-24, S3 15-20, TTS Quattro 16-23, TT Quattro 16-23; VW Arteon 22-23, Golf 15-18, Golf Alltrack 17-19, Golf R 15-24, GTI 15-21, Jetta 19-24, Golf SportWagen 15-19