The DOB-80 is a high quality German GM tube. Like the DOB-50, it was designed in Germany for production in Poland and has only recently been made available to the public by the Polish military. It is sensitive to both Beta and Gamma radiation, making it nearly perfect for use in most modern Geiger counter circuits.  https://www.youtube.com/watch?v=S_wvZwzrf28   https://dozymetria.wordpress.com/tag/dob-80/