1Made of high quality stainless steel material, lightweight, anti-rust and durable. 2Convert the M18x1.50 oxygen sensor threaded port to a smaller M12x1.25 thread pitch. 3Commonly used fit for Nissan SR20DET motor with aftermarket exhaust turbo elbow that normally comes with the bigger O2 sensor thread hole when using with the smaller O2 sensor. 4Detachable design, it is compact, safe and leak-free. 5Good sealing, which can eliminate leakage caused by poor welded joints.1 x O2 Bung Reducer AdapterCondition: 100% New_x000D_Item Type: O2 Bung Reducer Adapter_x000D_Material: Stainless Steel_x000D_Color: Silver_x000D_Fitment: Fit for Nissan 240sx w/ SR Motor RWD 1Made of high quality stainless steel material, lightweight, anti-rust and durable. 2Convert the M18x1.50 oxygen sensor threaded port to a smaller M12x1.25 thread pitch. 3Commonly used fit for Nissan SR20DET motor with aftermarket exhaust turbo elbow that normally comes with the bigger O2 sensor thread hole when using with the smaller O2 sensor. 4Detachable design, it is compact, safe and leak-free. 5Good sealing, which can eliminate leakage caused by poor welded joints.1 x O2 Bung Reducer Adapter