Gentec 853 Series Designed for medium to heavy duty gas welding, cutting and heating applications, these single-stage regulators provide top performance in a wide variety of industrial and laboratory applications. 9/16in-18LHM, Gas: Acetylene.Features: Self re-seating external pressure relief valve on oxygen models Forged brass body and housing cap Conforms to CGA E-4 standard for gas pressure regulators Stem-type seat assembly for more reliable performance Delrin cap bushing for smooth adjustment 2-1/2in gauges for easy reading 2-3/4in diaphragm Weight: 3 lbs 8 oz