This replacement hydraulic seal is manufactured as a compatible alternative to OEM part number 0509012129 and is used in the hydraulic systems of underground drilling equipment. Made from durable rubber material, it is designed to withstand hydraulic pressure, temperature variation, and continuous operation. The seal plays a critical role in maintaining system integrity and preventing fluid leakage. It is suitable for applications including COP-2160, COP-2560-PR, COP-SC25X-HE, and RD-14U drilling configurations.