The O-ring H 21434 is a high-performance elastomeric sealing element used to achieve leak-free operation in pressure and fluid connections within the Sulzer ASL25 engine. Designed to retain its shape and elasticity under thermal cycling, vibration, and exposure to oil and fuel, it ensures a secure and flexible sealing interface between mating components. Despite its compact dimensions, this O-ring plays a vital role in preserving system pressure, preventing fluid loss, and protecting internal parts from contamination. Its durability and reliable sealing characteristics contribute significantly to stable engine performance and extended service life.