Removed from my SQ5 before trade in. Sound booster piggybacks on to your existing module and give you a louder and way better sounding exhaust note for the SQ5 or A6 bi-turbo with drive select. i had the maserati map loaded on to this and it was a perfect upgrade in sound. like a refined but angry v8. Cost me £250, comes with original bag and instructions plus receipt. CHeapest exhaust mod. transforms the sound of the car and driving experience. Looking for £150 plus postage?