I use the 18x24 Itoyas for DPS and similar medium-sized poster pieces. But I had Gerber custom cut half-backs to 18x24 to use as backing boards since there is a danger of handling damage with all of the flex. Last, I cut an extra piece of foamcore I had laying around to a larger width. I hang the whole folio on this. This is important if you aren't storing it flat because it eliminates that warp/roll you get from Itoyas that stand on their spine. This is a pretty good system. I have on