Center Joint Seal Kit for Construction Machinery 31M8-51530 Excavator. Premium quality hydraulic seal repair kit for construction machinery from topsealkit, delivers reliable sealing performance, superior wear resistance, and precise fit for Hyundai R55-7 R55-7A excavators. This OEM equivalent turning center joint seal kit (Part No: 31M8-51530) is engineered to withstand extreme working conditions, ensuring zero fluid leakage and minimal maintenance costs for construction, landscaping, and small-scale civil engineering applications.