24 x 36 Black Corrugated Plastic Panels, 3/16-inch Thick, Great as Poster Backer - Set of 2 Set of 2 corrugated plastic signs are perfect for creating a double-sided presentation. 24 x 36 poster boards fit a variety of frames and sidewalk signs. 3/16-inch-thick boards are sturdy yet lightweight. Black color matches black sign frames and A-frame displays. Displays2go SKU#: CRP2436BLK