The Maxitrol R5310-48 Orange Spring is a replacement regulator spring designed for compatible Maxitrol RV53, R600, and R600S gas pressure regulators. It provides spring tension required to regulate downstream gas pressure within a 4–8 inches water column range, supporting consistent fuel delivery to connected gas-fired equipment. It is commonly used in commercial and industrial HVAC h... https://www.partshnc.com/r5310-48-maxitrol-4-8-orange-spring-r600