Flow adjustment device, comprising: - a containment structure extended along an extension direction between a first and a second end portion (2a, 2b), said containment structure comprising: ∘ at least one top wall at the first end portion; ∘ at least one axial outlet at the second end portion; ∘ at least one radial inlet at an intermediate portion of the containment structure extended in interposition between the first and the second end portions (2a, 2b); - a transmission member having a control portion, traversing the top wall of the containment structure, and a hollow portion, which defines a passage configured for placing in fluid communication the inlet with the outlet of the containment structure wherein the transmission member is at least rotatably movable, with respect to the containment structure, around the extension direction, wherein the hollow portion is at the upper part delimited by the control portion; - a differential pressure regulator operating between said inlet and said outlet, wherein the differential pressure regulator operates at the intermediate portion of the containment structure, and wherein the differential pressure regulator comprises: - a tubular body arranged coaxially with the transmission member and axially movable with respect to the latter; wherein the tubular body extends inside the containment structure for a main part of the intermediate portion in interposition between the radial inlet and the axial outlet; - a spring; - an elastic element having a radially inner edge constrained to the tubular body and a radially outer edge constrained to the containment structure; characterized in that the hollow portion extends inside the containment structure for a main part of the intermediate portion of the containment structure, and wherein the spring is radially interposed, between the transmission member and the tubular body. - a containment structure extended along an extension direction between a first and a second end portion (2a, 2b), said containment structure comprising: ∘ at least one top wall at the first end portion; ∘ at least one axial outlet at the second end portion; ∘ at least one radial inlet at an intermediate portion of the containment structure extended in interposition between the first and the second end portions (2a, 2b); ∘ at least one top wall at the first end portion; ∘ at least one axial outlet at the second end portion; ∘ at least one radial inlet at an intermediate portion of the containment structure extended in interposition between the first and the second end portions (2a, 2b); - a transmission member having a control portion, traversing the top wall of the containment structure, and a hollow portion, which defines a passage configured for placing in fluid communication the inlet with the outlet of the containment structure wherein the transmission member is at least rotatably movable, with respect to the containment structure, around the extension direction, wherein the hollow portion is at the upper part delimited by the control portion; - a differential pressure regulator operating between said inlet and said outlet, wherein the differential pressure regulator operates at the intermediate portion of the containment structure, and wherein the differential pressure regulator comprises: - a tubular body arranged coaxially with the transmission member and axially movable with respect to the latter; wherein the tubular body extends inside the containment structure for a main part of the intermediate portion in interposition between the radial inlet and the axial outlet; - a spring; - an elastic element having a radially inner edge constrained to the tubular body and a radially outer edge constrained to the containment structure; - a tubular body arranged coaxially with the transmission member and axially movable with respect to the latter; wherein the tubular body extends inside the containment structure for a main part of the intermediate portion in interposition between the radial inlet and the axial outlet; - a spring; - an elastic element having a radially inner edge constrained to the tubular body and a radially outer edge constrained to the containment structure; characterized in that the hollow portion extends inside the containment structure for a main part of the intermediate portion of the containment structure, and wherein the spring is radially interposed, between the transmission member and the tubular body.