The Fisher R122H voltage regulator is approved by Underwriters Laboratories (UL) for use in LPG two-voltage regulator systems. Designed to be used as a voltage regulator in civilian installations, the R122H's compact size makes it perfect for compact installations. Stainless steel internal parts and corrosion resistant coating make it a recommended replacement life of up to 20 years. The non-adjustable set point of the voltage regulator is actually tamper-proof. The inlet and outlet are equipped with pressure gauge holes for easy system testing. Large entrance and exit spanner planes facilitate installation, even in underground storage tanks. Outlet pressure set point is always maintained at the factory setting of 10 psig / 0.69 bar. Excellent release performance exceeds UL requirements and provides double failure overvoltage protection when used in conjunction with Fisher R600 two regulator. The regulator uses fluorine rubber valve pads for excellent closing performance and durability even in polluted gas media. The release hole is connected with 3/8 inch NPT thread for easy installation of the release pipe. The large size fabric - reinforced diaphragm allows for precise adjustment. Large port sizes help minimize freezing problems.