Best Vent/Rain Covers to Install over Factory Vent Fans???

Our factory vents are Fantastic Vents, I’ve also not found rain splashing in. Regarding screens, the vents have them, but I recently learned the clearance between the trim and vent is large enough to let small bugs inside the fifth wheel. A bead of color matched caulk solved that problem. The optional screens might be able to keep the smaller ones off, but not as inexpensive as caulk and the caulk wouldn’t effect airflow