The double stage automatic changeover regulator Type 528B is a combination consisting of an automatic changeover working as a 1st stage coupled to a 2nd stage regulator. The automatic changeover ensures continuous gas flow, automatically changing the gas withdrawal from the empty “service” cylinder to the full “reserve” one. The full-empty indicator incorporated into the bonnet of the automatic changeover indicates the exhaustion status of the “service” cylinder. The indicator color changes from green to red, when the “service” cylinder is exhausted. The rotation of the automatic changeover handle to the full “reserve” cylinder restores the green color on the indicator. Since the regulator body is made of zinc alloy, it is necessary to use the proper plastic mounting bracket for this type of regulator. Cavagna Group, Automatic Changeover Type 528B, 25-250 PSIG Supply Pressure, 100 PSIG Inlet Pressure 140,000 BTU, Outlet Pressure 11 WC, Propane Gas, Reinforced Diaphragm, ZAMAK Body, Wall mounting bracket.