The answer is 4 with.my car. 1st mechanic didn't fit clip properly when I had new turbo boodt pipe fitted so had loss of power again. Took it to a garage needed 2 mechanics to fit as they said it was a bit fiddly. that was 2 days ago. Drove about 250.miles and came off again as lost power again.Called RAC and he managed to get it on but needed my help. He reckons the genuine turbo boost pipe comes with a new modified clip and reckons the 1st mechanic probably kept it and fitted the old clip.not sure about this does anyone know.