1.2709 (MS1) is an 18% nickel maraging steel powder engineered for laser powder bed fusion and other additive manufacturing processes. After a simple age hardening heat treatment, it achieves exceptional tensile strength and hardness with good toughness, making it ideal for tooling inserts with conformal cooling channels, precision dies, molds, and high-strength structural components. Qualified to ASTM A646 and AMS 6514, it is used across aerospace, automotive, military, and general industrial tooling applications where additive processing enables complex geometry that is impractical to machine from wrought stock.