Pinit BACKINGS for One Sheet Posters. 27-1/4 x 40". .125" thick "Banner Blue" Corrugated Cardboard. Acid free & Buffered. Indefinite Storage. SKU: KOSPAC40 (0)No Reviews yet Add to Shopping Cart Details **NEW SIZE** MUSEUM GRADE One Sheet Poster Backings 27-1/4 x 40" .125" thick Archival Corrugated Cardboard. Acid-free & Buffered. "Banner Blue". Details Back Details**NEW SIZE**MUSEUM GRADE One Sheet Poster Backings 27-1/4 x 40" .125" thick Archival Corrugated Cardboard. Acid-free & Buffered."Banner Blue". Reviews 0 Back Ratings & ReviewsNo reviews availableBe the first to Write a Review