We live on a 40′ rv and came home after 4 summer months to find black mold inside the rv. We used the Mold Bomb and it worked great. We then washed down all of the surfaces. The product works great! We have a dual reverse cycle heat pump in the basement which uses a metal furnace duct in the floor. I also used a second bomb to spray into the cold air return while the ac was running. I covered all of the vents except the last one at the end of the duct. The vapor went through the entire duct system and out the other end. You could smell the product there and it ultimately set the carbon dioxide sensor off. I also used the spray liquid for the surfaces. Both products have a pleasant and clean smell and work great! Thanks