The blow off valve is a way to release air from the engine if the pressure gets too high. With a turbo, you might have to open the valve at some point in order to not blow the engine. But with the Turbo Blow Off Valve, you can open the BOV and have your engine get the extra boost you need. This is especially useful for cars that do not have a proper BOV.

The new design of the app allows you to choose your favourite sound for the BOV. 

You can also change the colour and size of the turbo.