Polish Forces

Polish 7PT tank

https://www.google.com.au/search?q=Wojsko+Polskie+sierpien+1939&ie=utf-8&oe=utf-8&gws_rd=cr&ei=o21ZVfHyLcmA8gXp3YCYAg#q=zdjecia+wojska+sierpien+1939

It's probably a test run.