The O2 sensor fixture contains a miniature catalytic converter designed to help maintain proper emissions system function if the main catalytic converter is damaged. This device helps prevent the check engine light from illuminating due to catalyst efficiency issues. Avoid using unreliable extensions, as they often fail to provide consistent results. This unit features a built-in mini catalytic converter for improved performance and reliability. When the primary catalytic converter is removed, the downstream O2 sensor may detect increased exhaust gas temperature and unburned fuel, which can trigger a check engine light with diagnostic trouble codes such as P0420 or P0430 (catalyst system efficiency below threshold). This adapter is intended to help address these types of emissions-related codes by simulating the presence of a functioning catalytic converter. In some cases, check engine lights are caused by O2 sensor irregularities, which may result in additional error codes. This unit is designed to assist with resolving certain code issues related to catalyst efficiency, including P0420. Features: 1. Precision-threaded design using specialized tools for accurate fitment. 2. Durable construction with high-quality materials resistant to deformation and corrosion. 3. Universal compatibility with most vehicles equipped with M18 x 1.5 O2 sensors. 4. Made from strong, long-lasting metal material. 5. Simple installation with direct mounting. Condition: New Type: O2 Sensor Adapter Thread: M18 x 1.5 Size: Approximately 1.85 x 0.98 x 1.18 inches Material: Metal Color: Silver Package Contents: 10 x Oxygen Sensor Adapters Note: The package includes only the items listed above. Other accessories are not included. Note: Lighting conditions and display settings may cause slight variations in color representation between the image and the actual product. Measurement tolerance: +/- 1-3 cm.