To keep your Solstro wood roof window looking beautiful for longer, you simply need to sand and then re-lacquer the wood with any water-based lacquer. Grease the hinges every 1-2 years.
The air filter can be removed and washed with ordinary household cleaners. Fully rotate and secure the window in cleaning position, then remove the filter from the filter rail.
You'll find a complete guide to cleaning and maintenance of this window here