If you’ve got a BMW 800 or 1200, or a KTM 1090/1190/1290, then you need a Guglatech Rally Raid Shield 4 Air Filter. This is the world’s first WET/DRY air filter.
Used DRY, it’ll filter out contamination as small as 30 microns.
Used WET, with a light coating of air filter oil, it’ll filter down to 10 microns.
It can be washed in the field with soap and water, then re-used over and over again. That means it lasts for a lifetime.
Read this article to learn more. Guglatech Rally Raid Ultra 4 Air Filter 11-27-18