This is a market research notice to identify potential sources capable of fabricating, testing, and delivering MK19 40MM MOD 3 and MOD 4 Grenade Machine Guns, associated spare parts kits, barrel assemblies, special tools/gauges, and contractor-led operator/maintainer training. The training could potentially take place both within and outside the continental United States. If a contract materializes, the First Article Sample would be due 270 days after award, with monthly production deliveries of 75 to 130 weapon systems beginning 60 days after its approval. The notice seeks detailed information on production capabilities, quality assurance, and rough pricing. Responses are due by 4:00 p.m. EST on January 30, 2026.