I've had these for several months now and LOVE them. I have older single pane glass in the bathroom around the tub that is awful on our AC bill. I'm in Arizona and this summer, with these hung and kept closed during the day, we have had a HUGE savings on our cooling costs. I'm excited to see how they work in keeping the bathroom warmer in the winter. I installed them myself in about 10 minutes. Fit nicely inside the window frame for a sleek look.