AVOTurboworld`s registered design silicon inlet hose kit for the 2015+ WRX, Forester XT 2013+, and 2010-2013 Legacy GT BM/BR with three goals in mind. The OEM pipe is prone to brake were the BOV is mounted we fixed this by making it one peice pipe from 5 ply silicone with wire reiforcement. And the outher goal`s were to make the pipe strong enough to resist sucking shut on even the largest of turbochargers. The other was to make the largest pipe that could fit in the narrow space available. Why are we so concerned about strength? If your setup is stock, there is not much to worry about at all. But if you are running higher boost levels, or larger turbochargers, the turbo can literally suck the pipe shut and especially if you are still using the stock airbox. This situation is not only bad for power, but can literally destroy a turbocharger! Is bigger better? Yes! If you are planning on making more power out of your turbocharged car, you need to flow more air, period. Bigger intercoolers, turbochargers, and exhaust systems will not work if you do not suck in enough air. That is why we designed our inlet pipe so large. So even if you are running our AVO turbocharger kit, you will not be let down before the air has even reached the turbocharger!