This is a photo-etched detail parts set for detailing AFV kits.
Toward the end of WWII, the fuel-hungry German Army turned to "Stadtgas" to fuel its training tanks. The term simply means "city gas" and refers to municipal gas used in homes for cooking and heating. When mildly compressed, this type of gas becomes liquid, allowing to be stored in metal bottles. There are several interesting photos showing these bottles mounted on the backs of Panther Ds used to train new tank drivers.
Voyager hits it on the head again with this comprehensive set. Composed of SEVEN frets of photo-etched material, the set encompasses all the relevant Panther D details as well as the associated hardware for the Stadtgas conversion. Six resin gas bottles are included with their delicately molded valves. As always, Voyager adds various thickness plastic rod and wire to add to the detail fun. Also found in the set are parts to construct the fender distant markers seen on non-combat Panthers.