Airbox Sound-Intake Insert

Two-piece intake opening developed and physically fitted to the airbox of a BMW F20/F21 1 Series. The creator states that it is intended to add intake sound, not power; the cutting profile and finished insert are both included. Keep the factory filter path intact, use an engine-bay-temperature-resistant material, de-burr the airbox opening, and inspect the installation for secure retention and contamination paths before running the engine.