The quality specification document, code 10.09412-3021-1.0, outlines the rigorous manufacturing and inspection standards for the MAN L21/31 engine. This specification ensures that all components, from castings to precision-machined parts, meet strict criteria for material integrity, dimensional accuracy, and performance reliability. It serves as a critical reference for OEMs, maintenance teams, and suppliers to guarantee consistent quality throughout the engine’s lifecycle and to uphold MAN Diesel's global reputation for engineering excellence.