2011 passport 290 BH roof damage
Probably a vent cap for a holding tank. Fairly common part and your local RV parts store should have them in stock. Easy to install, just carefully peel off the sealant, remove 3 screws. Put butyl tape on the bottom side (should be included with the new part) and screw back down. Don't forget to get some Dicor sealant to cover the screws.
2012 Copper Canyon 273FWRET being towed by a 1994 Ford F350 CC,LB,Dually diesel.
Airlift 5000 bags, Prodigy brake control, 5 gauges on the pillar.Used to tow a '97 Jayco 323RKS.
Now an RVIA registered tech. Retired from Law enforcement in 2008 after 25+ yrs.