Apollo Saturn check valve, measuring approximately 4.5″ x 4.5″ x 2.25″, etched on the body: "Valve, Check, N2O4, Vapor, GN2, Assy No. A90158 DAC Spec 1A79530-501?Contr. No. NAS 7-101?Ser. No. 1029, Date 3/66." The central diagonal tube is marked to indicate direction of flow. In fine condition.
