The MS28775-331 is an aerospace-standard O-ring sealing element (packing) used in aircraft hydraulic, fuel, and pneumatic systems. It provides a reliable pressure-tight seal between mating components such as fittings, valve bodies, pumps, and actuator housings.

This O-ring is a direct functional alternative to AN6227B34, offering equivalent dimensional fit and sealing performance for approved aerospace maintenance and overhaul applications. It is widely used in both static and dynamic sealing environments depending on system design requirements.

Manufactured to MS specifications, it is typically made from FKM (Viton-type) or equivalent high-performance elastomer, providing strong resistance to aviation fluids, hydraulic oils, fuels, and temperature extremes.

Key features include:

MS28775-331 aerospace O-ring seal
Alternative to AN6227B34
Used in hydraulic, fuel, and pneumatic systems
Provides reliable leak-proof sealing
Resistant to aviation fluids and oils
High pressure and temperature capability
Suitable for vibration and cyclic loads
FKM (Viton-type) elastomer construction
Used in valves, fittings, pumps, and actuators
Direct replacement per MS aircraft hardware standards