Covered goods wagons are almost as old as the railway itself and are primarily used for the transport of general cargo. In the 1950s, the Deutsche Reichsbahn could only maintain the demand for these vehicles by converting and modernizing older G-wagons. In 1966, the RAW "Einheit" Leipzig began constructing a prototype wagon of the Glmms type with corrugated metal walls, which were lined with wood on the inside. This design went into series production at the Gothaer Waggonfabrik starting in 1968 and was designated as Glmms 14.05 (renamed Gbs 1500 in 1977). The welded structure, with its distinctive corrugated side walls, extended down to the lower edge of the outer longitudinal frame beams and was connected with box profiles. This allowed for the elimination of conventional wagon body supports. The majority of the wagons were built with reinforced doors. The floor was suitable for loading with forklifts and was made of pine planks. By 1983, over 17,000 units of the Gbs 1500 design had been produced, including various versions as thermal protection and express goods wagons. Some subclasses were equipped with brake platforms and heating lines. Due to a lack of production capacity in their own factories, wagons were also built in Serbia, Romania, and even Spain. The wagons were operational beyond the borders of the GDR due to their RIV, MC, or OPW interoperability and were frequently seen in freight trains of other railway administrations even before the reunification. These wagons remained in service within the DB AG fleet until the late 1990s after reunification, with the last ones being retired in 2007.