This hydraulic seal is designed as a compatible replacement for OEM part number 0508110139 and is used within the hydraulic system of underground drilling equipment. Manufactured from high-quality rubber materials, it ensures effective sealing performance to prevent hydraulic fluid leakage under pressure. The seal supports stable system operation and helps maintain hydraulic efficiency in demanding underground environments. It is suitable for use on ST18 and ST14 equipment, providing reliable performance during routine maintenance and hydraulic system servicing.