Popular upgrade for track cars. Replaces the standard airbox with a performance optimized version from the GT3 Touring. The internal air channels are smoother and streamlined, especially when compared to the normal Carrera airbox. Replaces the standard two flat panel filters with two factory cone BMC filters for maximum air flow. Some modifications are required, and sound symposer vacuum lines must be plugged/sealed to prevent vacuum leaks (the sound symposer is eliminated). Professional installation recommended. Intended for 2013-2016 911 Carrera, GT3, & 911R models.