This is a total small business set-aside Navy procurement for a complete stem assembly for a size 1½-inch ball valve, manufactured to Electric Boat drawing 2445483, Assembly GH, with additional dimensions from Newport News drawings 255980 and 255588, and it is designated Special Emphasis/Level I SUBSAFE material for a crucial shipboard system. The assembly includes a QQ-N-286 Alloy UNS N05500 stem requiring annealing/age hardening and ultrasonic inspection, an ASTM-B505 UNS C90300 nut, and a bushing; weld repair is not allowed and strict thread and O-ring/sealing-surface inspection applies. The contractor must maintain an ISO-9001 or MIL-I-45208 quality system, perform traceability and material certification, provide certificate of compliance and test certifications, and support Government quality assurance at source. The award will be bilateral, DO-rated under DPAS, and evaluated with past performance by NAVSUP WSS Mechanicsburg; inspection/acceptance point is TBD and FOB destination. The warranty is one year from date of delivery, and offerors should expect configuration control, waiver/deviation, ECP, mercury-free, and electronic signature/certification requirements.