Open Box Oceanic FDXI 1st Stage, DIN, BKThe cold forged, over balanced diaphragm FDX i first stage is environmentally sealed. The in line design limits the pressure loss inherent in L type first stage designs making the FDX i more efficient and lighter due to its compact form. The FDX i in line design provides an improved flow rate, greatly reduced weight and more ergonomic port positioning for better hose routing when compared to the classic right angle first stages.