Hi Louie, That actually works better for me, with the CSS because the bigger image covers several thumbnails at the same time you don't get to see all the pictures. The big picture covers 6 thumbnails at the same time. The reason why I didn't use JS before is because I don't know much about it. I am testing with one thumbnail and one image and they are both the same size, but the original two pics have different height and width. Do you know what line contains the info for height and width for the bigger image? Thanks in advance, Paolo