Enamel advertising sign for Novex roofing sheets, manufactured by Emaillerie Koekelberg in 1958, the year of the World Exhibition in Brussels (Expo 58).
 
Novex underroof panels were made at SVK (Scheerders - van Kerckhove) in Sint-Niklaas-Belgium. SVK has been a manufacturer of building materials since 1905. 

Considering its age, the board has some signs of wear (see photos).