Center Joint Seal Kit for Case U39026 Excavator. Premium quality hydraulic seal repair kit for construction machinery from topsealkit, delivers excellent sealing performance, exceptional wear resistance, and perfect OEM compatibility for Case Crawler Excavator 688C. This aftermarket premium swivel/center joint seal kit is engineered to provide reliable hydraulic system protection, ensuring zero fluid leakage and reduced maintenance costs for construction, mining, and civil engineering applications.