May 15, 2017 Plastic Signs You can ensure full engagement within your corporate building by providing your clients and employees with way-finding signage that will help guide them to their destination. Coroplast: Good for yard signs, job site signs and political signs. Extremely durable since its waterproof and UV resistant. Foam PVC: Excellent option if you want double-sided graphics and unique cut shapes. Polystyrene: Thin material for show graphics, wall panels, custom ceiling danglers, and in-store displays.