This model dates back to the very early days of N scale. The first version came out in the early 60's and sports flat/featureless truck sideframes, chassis clips clearly visible through the carbody sides, featureless chassis bottom, primitive endrails, and no ladders. The couplers are simple bent hooks that are mounted to the chassis. The trucks are held to the chassis with rivets.
A second version came out in the mid-60's. This one is basically the same as the first version excepting that the bizarro metal hooks have been replaced by an early version of the classic "Rapido" coupler (this version having strange looking vertical pegs sticking up from the right tip). Also, the truck sideframes have been upgraded (now with actual detail). The trucks are held to the chassis with screws.
This model was revised yet again in the late 60s. And although the shell is pretty much identical to the one used in the first two versions, the chassis is completely new. The "see through the shell" clips are gone, the underside has actual detail, and the primitive step/endrail assembly has been replaced with more prototypical handrails, ladders and steps. The trucks are also completely redesigned, sporting traditional Rapido-style couplers. The trucks clip to plastic posts on the chassis.
This particular model (regardless of version) seems to be fairly scarce. Which leads me to beieve that it was probably discontinued fairly early on. 70s? 80s? I dunno, your guess is as good as mine. All versions are stamped "Arnold Rapido - Made in West Germany" on the bottom.
This ubiquitous eight window design has been a staple of N scale since the beginning, with virtually every manufacturer offering one version or another of it. It is based on the "ATSF 1900 Series" prototype. The unique feature of this particular model is the smokestacks - being decidedly short and stubby.
Known roads - Plain red, NYC, SF, UP