so i built this one box of mine to learn nose and tail presses among other things. i wanted it to have some difficulty so i didnt want just a butter box. The rail/box is 2 feet tall at the beginning and one foot tall at the end. Its also 4 inches wide at the beginning and two feet wide at the end. the overall length is about twenty feet. it works great for presses because the rail widens as your sliding down it so you can really press hard.
ill post pics/video when i find them, but i havent seshed the box in a while.