Ordering Description Product number Description: ESL4-15-250 EDGE Series Pipeline Regulator- Air, CO2, N2O, Inert Gas Product number: 0781-5190 Description: ESL4-125-250F EDGE Series Pipeline Regulator- Hydrogen, Methane, Natural Gas, LP Gas Product number: 0781-5211 Description: ESL4-15-250A EDGE Series Pipeline Regulator- Acetylene Product number: 0781-5208 Description: ESL4-80-250F EDGE Series Pipeline Regulator- Hydrogen, Methane, Natural Gas, LP Gas Product number: 0781-5210 Description: ESL4-125-250X EDGE Series Pipeline Regulator- Oxygen Product number: 0781-5214