These cheapie Evemodel N scale freight cars first started appearing circa 2020 and, at least as of this 2023 writing, not much is known about them (apart from speculation that the models are probably knock-offs of cars sold by one of the major mfr's).
Evemodel doesn't provide any information on the prototype for this model (if there is one), but mechanical reefers like this one first started appearing circa 1958.