Will this filter fit into my factory air box without any brackets or adapters?

Yes. This is a direct OEM replacement — it slides into your existing housing and seals at the factory mounting points. No brackets, no adapters, no fitment guesswork.

How often should I replace this filter?

That depends on your driving conditions and local air quality. Check your BMW owner's manual for the recommended service interval — typically 15,000 to 30,000 miles for diesel engines.

Does this come with any hardware or gaskets I need to know about?

The filter assembly ships as pictured. Your factory air box will have its existing gasket and clips — you reuse those. No additional hardware is needed for installation.