7820 - Mail Van
In 1980, the LEGO Train line was refreshed and re-launched into what has become known as the grey era. That first wave of sets came with a series of stand alone "extra" sets, and this 7820 was one of them.
The A-model represents a mail van, which is divided into two parts. The presence of the smaller crew compartment indicates that the mail van was not only used for transporting mail, but it was also used for sorting mail during transport, which is presumably done by the chap with the blue cap. This is also indicated by the presence of a sorting table inside the cargo hold.
This set is one out of three mail wagons from the 1980s Trains sets, together with set 7819 from 1983 and the postal wagon from set 7722, introduced in 1985. Of the three, 7820 is the only to be released before the introduction of the Postal subtheme in 1982 (starting with sets 6362 and 6651). As such, it's the only one not to feature the horn-and-envelope logo and the white 2x1 tiles with a letter printed onto them.
This wagon was the third set from 1980 to come with the big 6x28 train baseplate. The cargo hold is accessible through 2 red "shed style" doors, which are also used in sets 7822 and 7730.
This wagon looks pretty good when added to the 7740, particulary before the introduction of set 7819 in 1983. But it looks even better when put behind a 7750, as suggested in some contemporary ads and ideas book 7777.
For the B-model, 7820 was redesigned into a dump car wagon with a brakeman's cab, all in red, which fits perfectly with the B-model of 7740.
Packaging (3D scan)
click to view the 3D scan