For all, be warned about the Mushroom Attic Vent Covers, these are the approx 6 inch diameter vents, one forward and one aft to vent the attic area. These covers thread onto a stud and are only hand tighten and can vibrate loose and eventually disappear (lost one on our Montana). My fix is to add a little silcone sealant/RTV to the threads and reintall the cover snug, helps hold them in place but can still be removed if they need replacement.
Michelle & Ann
2018 Chevy 3500HD Crew Cab High Country DRW, D/A, 2016 RW39MB, Dual ACs, Auto Level, Auto Sat Dish, Stack W/D, King Sleep #, 17.5" Sailuns w/Disc, MORryde IS & Pin, Comfort Ride Hitch, 5.5 Onan, Res Fridge & Induction Cook Top