glass flow meter for air, oxygen, hydrogen: 1.high quality gas ... 2,measure and control flow rate 3.various flowmeter Portable glass flow meter for air, oxygen, hydrogen 1.high quality gas ... of NT-4T,6T,8TFlow Meter With value Value Fitting Float O-ring T- with O- No Brass Ss 1. ABS ... ball PTFE 1-Silicon rubber 2-Fluorin rubber 3-Butyl glass flow meter for air, oxygen, hydrogen