Product review (5 stars): Perfect on my roof above my fart fans
Theses are an elegant solution if you care what your roof looks like.  I had three six inch vents from bathroom fans penetrating my roof and I chose to finish with these.  Roofer installed easily and I'm confident they will never leak or be a problem.  I did however, replace the screens myself with a finer mesh to prevent bees and othe insects from visiting.  I also repainted them! Then my roofer repainted them again!  I like that they have their own damper that works real good.  Also the metal is a heavy enough guage that its unlikely they will dent from normal impact.  They look great installed, my roof looks better than all my neighbors!