aFe 59-10081 Magnum FORCE Cold Air Intake System Spare PartsaFe 59 10081 Magnum FORCE Cold Air Intake System Spare Parts Allows For Use of Euro MAF Sensor: This adaptor allows for the use of high performance Euro style MAF sensors on the US Domestic Market (USDM) BMW E36 M3. 88. 9mm to 71. 1mm Reducer: This coupling's inlet diameter is 88. 9mm, matching Euro MAF sensors, and reduces down to 71. 1mm to match domestic style throttle bodies. Polyurethane Construction: Its flexible polyurethane construction is