The J304βγ China-made glass modern GM tube is very sensitive to both Gamma and Beta radiation. It has a screw-type base for easy mounting in a Geiger counter. Like the J302βγ, it uses a metalized film coating on the inside of the glass envelope as the cathode. It became quite popular in Japan, especially after the 2011 Fukushima disaster. This is an excellent all-around tube used in a variety of popular commercially employed handheld portable and laboratory Geiger counters.