Twinstar 900s how to tell version?

[jwmachon]

Looking at buying a twinstar 900s possibly 2nd hand

How can you tell the difference between v1, V2, and V3

Is it the 3 digits after the 900s

Thanks

 

[NinjaMonkey]

 

[NinjaMonkey]

Says on the top, I'm sure the older ones do except the 1st that just says 900s