From a quick search of the Gear store, it looks like it is from either the "Rugged" line or the "Worn" line. Keep in mind, there are hundreds of watch faces. Your best bet is to go to the Gear store and look through the watch faces.
If you don't have Facer installed, I recommend it as well. Install it on your phone and then the companion app on your watch to allow the Facer watch faces to be downloaded to your watch.