0.9mm thick aluminium with engineering grade reflective finish Suitable for both indoor and external applications Excellent weathering and UV resistance provides a long-life product Advise drivers of height restrictions - reflective finish maximises visibility when driving in night conditions as light is bounced back off the sign. Please state required headroom height when ordering Material Explained Aluminium: 0.9mm.9mm aluminium with a gloss white powder coated face. Suitable for both internal and external applications. Excellent weathering and UV resistance provides a long-life product.