Battelle Energy Alliance is seeking qualified vendors to design, manufacture, test, and deliver four 20-inch, 300-lb tilting-disc check valves for the Advanced Test Reactor at Idaho National Laboratory. The valves must meet stringent nuclear safety requirements, including ASME Section III, Division 1, Class 1 standards, and include integrated hydraulic dashpots and position indicators. This Expression of Interest is the first step before a formal solicitation, with selected vendors potentially invited to participate in a future Request for Proposal. Performance of services will be at the vendor’s facility, with delivery to the Idaho National Laboratory. No budget amount or submission timeline is specified in this description.