Differential, Jorlon Diaphragm The Mark 53 and 54 Series transform challenging differential pressure control into reliable, repeatable operation. By maintaining a precise pressure differential between inlet and signal pressure, these valves enable sophisticated process control strategies – from maintaining consistent pressure drops across filters and strainers to managing complex reactor pressure profiles. When your process depends on maintaining exact pressure relationships, not just absolute pressures, these differential pressure valves deliver the control intelligence you need.