The seal ring, code 100100, is a precision-engineered sealing component used throughout the MAN L21/31 engine to prevent leakage and maintain the integrity of critical mechanical and fluid systems. Installed between mating surfaces or around rotating and stationary components, it creates a reliable barrier against the escape of lubricating oil, fuel, coolant, or compressed air while preventing contaminants from entering the engine. Designed to accommodate vibration, pressure fluctuations, and thermal expansion, the seal ring ensures consistent sealing performance under demanding marine and industrial operating conditions. Manufactured from high-quality wear-resistant and chemically resistant materials, it contributes to improved engine efficiency, lower maintenance requirements, and extended service life of vital engine assemblies.