Buyers must prioritize OEM-equivalent specifications to ensure mechanical compatibility. For engine components like pistons or valves, verify the material grade (e.g., high-silicon aluminum alloy) and heat treatment standards. For transmission parts, ensure the CVT (Continuously Variable Transmission) components match the specific Nissan Tiida generation (C11, C12, or C13) to avoid synchronization issues. Always request technical drawings or CAD files to confirm dimensions like bore size and stroke.