I packed a show that needed to travel vertically and used a combination of the standard 2 pound Etha and 9 pound rolled Etha. The roll was a sheet of 9 pound foam 3/16 of and inch thick by 60 inches wide. I glued the slots to 1/2 inch foam-core. The 2 pound was cut into strips 1x 1 inches and the 9 pound cut to just over the thickness of the frames. Care had to be taken while gluing up the slots so that they remained parallel so that when we cut the board in half we got matching book ends. The crate was lined in two inch urethane foam with the slot boards glued to them. The show had two venues and the foam looked exactly like it looked when shipped with no tears. I remember purchasing the foam locally in Philadelphia from a Kelly, but agree that Uline will probably carry it as well.