This Chinese-made model replaced the old Mehano/Yugoslavia "standard cupola" caboose originally imported by Model Power. And as such, I'm assuming it's some sort of knock-off of one of the earlier cupola caboose designs (either Roco, Atlas or Mehano). These models are simply stamped "Hong Kong" on the bottom. I'm not sure when exactly they first came into being, but my guess is sometime during the 1980s (or possible even the 1990s). As of this writing (2008), Model Power is still cranking these things out.
These models have metal wheels and truck-mounted Rapido couplers.
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.