A combination pressure regulator, comprising: - a regulator body having an inlet port on an exterior surface of the regulator body, and an outlet port on the exterior surface of the regulator body, - a first pressure regulator; and - a second pressure regulator; wherein an input portion of the first pressure regulator is in fluid communication with the inlet port, and an output portion of the second pressure regulator is in fluid communication with the outlet port; and characterized by: wherein the regulator body further has a combined inlet and outlet port on the exterior surface of the regulator body; wherein the first pressure regulator includes a first diaphragm, a first valve assembly movable by the first diaphragm, and a first biasing member that applies a first bias force to the first diaphragm to establish a first pressure regulator setting; wherein the second pressure regulator includes a second diaphragm, a second valve assembly movable by the second diaphragm, and a second biasing member that applies a second bias force to the second diaphragm to establish a second pressure regulator setting different from the first pressure regulator setting; and wherein both of an output portion of the first pressure regulator and an input portion of the second pressure regulator are in fluid communication with the combined inlet and outlet port, and/or wherein the output portion of the first pressure regulator is in fluid communication with the input portion of the second pressure regulator within the regulator body. - a regulator body having an inlet port on an exterior surface of the regulator body, and an outlet port on the exterior surface of the regulator body, - a first pressure regulator; and - a second pressure regulator; wherein an input portion of the first pressure regulator is in fluid communication with the inlet port, and an output portion of the second pressure regulator is in fluid communication with the outlet port; and characterized by: wherein the regulator body further has a combined inlet and outlet port on the exterior surface of the regulator body; wherein the first pressure regulator includes a first diaphragm, a first valve assembly movable by the first diaphragm, and a first biasing member that applies a first bias force to the first diaphragm to establish a first pressure regulator setting; wherein the second pressure regulator includes a second diaphragm, a second valve assembly movable by the second diaphragm, and a second biasing member that applies a second bias force to the second diaphragm to establish a second pressure regulator setting different from the first pressure regulator setting; and wherein both of an output portion of the first pressure regulator and an input portion of the second pressure regulator are in fluid communication with the combined inlet and outlet port, and/or wherein the output portion of the first pressure regulator is in fluid communication with the input portion of the second pressure regulator within the regulator body. wherein the regulator body further has a combined inlet and outlet port on the exterior surface of the regulator body; wherein the first pressure regulator includes a first diaphragm, a first valve assembly movable by the first diaphragm, and a first biasing member that applies a first bias force to the first diaphragm to establish a first pressure regulator setting; wherein the second pressure regulator includes a second diaphragm, a second valve assembly movable by the second diaphragm, and a second biasing member that applies a second bias force to the second diaphragm to establish a second pressure regulator setting different from the first pressure regulator setting; and wherein both of an output portion of the first pressure regulator and an input portion of the second pressure regulator are in fluid communication with the combined inlet and outlet port, and/or wherein the output portion of the first pressure regulator is in fluid communication with the input portion of the second pressure regulator within the regulator body.