The Z wave chip which is used for home automation is only made by a couple of licensed companies.
Then all the other companies that actually make devices like light switches or locks will purchase the Z wave chips from the authorized makers to include in their own devices.
The most current generation of the chip is the fifth generation, also called series 500 or the fancy marketing name of “zwave plus.”
There are some significant improvements in this chip over the prior generations (now called “classic Z wave”), in particular, longer transmission range and better battery Life for battery powered devices.
As far as telling what is the newest version of any given device, you generally have to go to the manufacturer’s website.
In the case of GE zwave devices, GE licenses its name to Jasco, and Jasco lists its products on the following site:
But any zwave plus model should be newer than any Z wave classic model. The logos are a little different:
