Coro-Flex is a fluted corrugated polypropylene sheet for short-term outdoor and indoor signs. The lightweight twin-wall board is waterproof and rigid for yard signs, real estate signs, and point-of-purchase displays and prints with screen and digital inks. Supplied flat by the sheet and in case packs in 4 mm and 10 mm flutes. Recommended for election, real estate, and event signage.