In the 1950s, the Cologne company Klosterfrau was going on a big advertising tour with their own design of a semitrailer. The company was producing a complete semitrailer, at the company Buhne in Berlin, on the basis of a Mercedes-Benz L312, whose single-axle trailer was similar to a show room and was promoting the product Melissengeist.

The optic of the now converted truck of the L312 was completely independent and only the Mercedes star was emblazoned on the big cooling grill at the front and was showing its Swabian origin. The trailer was attuned to the optic of its truck and was also realized in the company of Heinrich Buhne in Berlin.

In three-month cycles, the advertising truck was driving through the Federal Republic of Germany and was returning back to the Cologne plant to refill its shelves and sales counter. Inside the truck the customers could be advised and could buy the product as in a real shop. Furthermore, the trailer had generous glass cases installed on both sides, which also promoted Klosterfrau Melissengeist.

In 1963, the management decided that the advertising truck should drive to Spain and bang the advertising drums for Klosterfrau Melissengeist. As the product was bearing there the name Melisana, the whole truck was immediately repainted. The colorful truck was driving around in Spain in the following years until 1965 and caused big sensation because of its unusual and nice optic. Especially in the night, the trailer was a wonderful sight because of its built-in lights of the show cases and inside of the trailer.

Unfortunately the trace of the unique model has been lost after its Spain tour, as according to today´s view it would be called as a show truck.