Rare plexiglass advertising sign by Rob Otten, from 1963. Marking on the back is "Otten Plastic Brux. T.P.B. 139/186/63. The letters are made of red and blue plastic and are glued to the white plexiglass. The letters themselves are 5mm thick. The size of the sign is 60 x 14.5cm. There are 2 holes for hanging. I have never seen this sign before. .
