How can I tell 1) if this tile is "self-spacing" or has built in spacers . . . and 2) what grout line size I should use?

I'll be using these tiles on our backsplash. I have a box (8 tiles) that I got to look at, and they look lovely.

I need to choose grout line size and figure out if these tiles already have "spacers" built in . .. . I don't detect any nubs on the sides of the tiles. If I put them side by side on a flat surface, there is about a 1 mm space between the faces of the tiles, so I was wondering if that is some self-spacing design feature or just random chance, lol,

In any event, what grout line would be best? Any suggestion on grout color (a light grey?)?

Thanks!

Link below to 3x6 Dove Grey subway tie by MS International

http://www.msistone.com/3x6-handcrafted-tiles/dove-gray/

Thanks!