Pinit BACKINGS for Half Sheet Posters. 22 x 28". .125" thick "Banner Blue" Corrugated Cardboard. Acid-free & Buffered. Indefinite Storage. SKU: KHSPAC (0)No Reviews yet Add to Shopping Cart Details MUSEUM GRADE Half Sheet Poster Backings 22 x 28" .125" thick Archival Corrugated Cardboard. Acid-free & Buffered. "Banner Blue". Indefinite storage. Details Back DetailsMUSEUM GRADE Half Sheet Poster Backings 22 x 28" .125" thick Archival Corrugated Cardboard. Acid-free & Buffered."Banner Blue". Indefinite storage. Reviews 0 Back Ratings & ReviewsNo reviews availableBe the first to Write a Review