If so, then yes it’s compatible with SmartThings, it’s basically a Kwikset white labelled version. If it doesn’t detect the lock out of the box, you can always force it to the use the correct device handler or check out custom handlers like this one which can access advanced features (for the 620, that’s controlling Audio on the lock as well as enabling/disabling physical programming for security).
Also like JD said, you need to match up the region z-wave frequencies.
You can use this page to keep an eye on the cheapest deals available for various locks