The Relief Valve Retaining Bolt is a precision-engineered fastener designed for use in 1 1⁄4”-2” Zurn reduced pressure principle backflow preventers (model 975XL and 975XL2). This bolt secures the relief valve assembly within the backflow preventer body, ensuring correct alignment and a tight seal for dependable operation. By maintaining the integrity of the pressure zone, this bolt helps prevent leaks and supports consistent system performance.