I don't know what the movement is in that model, but, it is a safe bet it's not the SW500. I'd also guess it's not a Ronda movement or sites would be advertising that. It's most likely not an ISA or the back of the watch would say 'Swiss parts.' That leaves ISASwiss or ETA. Going only on what the watch seems to sell/sold for I'd guess ETA, probably the G10 series. . . nothing wrong with that. Know that this is a guess on my part and if you do pick up the watch I'd be interested it what the movement actually is. Good luck!