Not too loud and not too quiet, the W15-XS-HYB from TurboXS is the valve for you if you want an upgraded Blow Off Valve that you can hear when you want to but not when you don't. Designed specifically for the 2015 WRX using our all new "XS" BOV platform, this valve is designed to vent partly to atmosphere and partly back to the intake giving you the "best of both worlds". This valve comes complete with everything you need to replace your stock bypass valve. The XS platform adds incredible versatility to this Blow Off Valve. The modular design of the XS platform allows you to change both the inlet and the outlet of the valve by yourself. This means that you can buy this valve as a 50/50 Hybrid Blow Off Valve and then with the purchase of your vehicle-specific outlet and recirculating hose plug (sold separately), you can change the valve into a 100% Vent to Atmosphere Blow Off. It's like getting two valves for just a few dollars more than the price of one!