Victor 0781-0543 SR450E-580 Professional Single Stage Regulator has been recommended for applications where slight delivery pressure increases (due to decreasing cylinder pressures) would not affect the performance characteristics of the work or test results. The SR450 regulators are designed for heavy duty applications and for larger cylinders. There is a brass adjusting screw with a forged T-handle and a delrin insert bushing for durability and easier adjusting. The stainless steel diaphragm gives an accurate long lasting service and a stem-type seat mechanism for inlet pressure aids in sealing. For easy adjustment there is a stainless ball in key. The adjusting spring has been pretested for quality assurance and there is a die-forged brass body for extra strength. For optimum flow control a precision machined nozzle is used. There are three additional features that include an external self reseating relief valve, a sintered inlet filter and this regulator will deliver. The delivery range in PSIG is 10-200. The gauge range inlet is 4000 and the outlet is 400. The CGA inlet connection is 580 and the outlet connection is 5/8 inch – 18 F LH. Maximum inlet pressure in PSIG is 3000 and the flow coefficient in Cv is 0.27.