I was working on my houseplants. I had some square flower pots that were maybe 6-inch square. I could put a row of them inside a window frame and have a row of them fit exactly, snugly inside the frame. I think I was either planting seeds or starter plants because I couldn't see anything growing. I think initially I was wondering either if they were going to fit or how they were going to fit. It turned out that they were an exact fit.