Victor FM 147 Medium Capacity Two Gas Calibration Flow meter offers 15 -70 SCFH, 40 - 200 SCFH flow range for argon and helium respectively. Flow meter with 25 psig inlet pressure features 5/8" - 18" RH(M) inlet fitting and 5/8"-18 RH(F) outlet fitting. It is ideal for MIG/TIG welding and cover tube of the flow meter consist of overpressure protection. Flow tube and outer tube of the flow meter are made of impact resistant lexan.