We have 4 vent openings in our 33ft. 5th wheel and they let in a lot of light, cold air in the winter and heat in the summer. I'd had already tried the uninsulated roll up type and didn't like them at all as they didn't insulate much and they kept falling off the velcro and since the ceiling was white, and they were silver, they looked out of place & everyone noticed them. Then I saw these vent cushions in a camping world out west and decided to try one and see how they worked. The cushions were deep, fit right into the openings and even though they come with velcro to hold in place, I've never used it. They have stayed there through every rough road we went over in our 5th wheel the past 5 years. They are white in color on all sides but one and one side is a silver top lining that you turn up to the sky and the silver reflects the sun, cold and heat. They look good and blend in to the ceiling also. The only problem with the silver foil is that over time, (4 yrs.) the clear bubble wrap that's over the silver foil, deteriorates then the clear bubble layer and silver flakes off slowly. So I just replaced one of them and will do the rest soon. They have a zipper so you can take out the foam and hand wash if they get dirty also. I will continue to use these as long as I have a RV. My husband likes the one over the bed best as it keeps the light out when he wants to sleep late. They are Great!!