This cover works very well. I pull my seat off, take the filter out, put the cover on & wash the bike as usual. I spray my wash in the air box when its dirty & wash it out (Use a garden hose, not a pressure washer). My air box is cleaner than ever & I have not had a drop of water get through. The only thing I will say is to remove the air box cover directly after washing the bike. I was leaving mine on over night during hot weather & I started having problems with my carb. Not 100% that the cover was responsible, But my riding buddy & I started using this item at the same time & he too had carb problems after leaving the cover on. No biggie, the cover does its job, I love being able to keep my air box super clean. I would recommend this item!