Crystal clear viewing of 18x24 documents such as posters or art Keep your art, posters, or other memorabilia clean and safe Pack of 5 18x24 poster size document holders per box 12 mil thickness means better protection than other sleeves in the market All-new sealed poster size topload holders Protective sleeve toploaders are essential items when collecting photos. Sold in packs of 5, art size Guardhouse toploaders are 12 mil thick and measure 18 x 24 inches. Guardhouse toploaders are made of non-plasticized rigid vinyl and are designed to keep photos unharmed during long-term storage, at the same time as offering the collector great visibility of their collectible items. Guardhouse Toploaders#: 831. Size: 18 x 24. Sold in Packs of 5.