Buna-Nitrile Material Construction: Made of durable Buna-nitrile rubber (Buna-N), providing excellent resistance to a wide range of fluids including petroleum oils, fuels, and aliphatic hydrocarbons. This material offers reliable sealing performance in demanding industrial and mechanical applications. 50A Durometer for Optimal Sealing: Features a 50A durometer (hardness) rating that balances flexibility with resistance to compression set and penetration. The round cross-section creates an effective seal between cylindrical overlapping surfaces, preventing leaks in dynamic and static applications. Precision Dimensions for Reliable Fit: Manufactured to precise dimensions: 3-1/4" Inside Diameter (ID), 3-1/2" Outside Diameter (OD), and 1/8" Width (cross-section). These standardized measurements ensure consistent performance and compatibility with corresponding gland designs. Wide Temperature Range Compatibility: Suitable for use across an extensive temperature range from -30°F to 250°F (-34°C to 121°C), maintaining elasticity and sealing capability in both low-temperature and high-temperature environments without becoming brittle or degrading. AS568A Aerospace Standard Compliant: Our precision-molded Buna-N O-Rings are designed to deliver consistent performance under demanding conditions. Meeting the exacting AS568A Aerospace Standard, they offer a trusted sealing solution for industrial maintenance, automotive repairs, and equipment manufacturing—where durability and leak prevention are essential.