Arm Cylinder Seal Kit 4639938 9180579 For Hitachi Excavator ZX270 ZX270LC ZX280LC ZX280LCNFor Hitachi Excavator ZX270 ZX270LC ZX280LC ZX280LCN Arm Cylinder Seal Kit 4639938 9180579 See Details: ModelNum. Application CylPart# Code RodSize(in) Bore(in) Size Misc SerialNumber Part# ZX270, ZX270LC, ZX280LC, ZX280LCN ARM 4628581 P UB 10 100mm 145mm MonoBoom D04 08 , D05 01 HIT 4639938 EX270 5, EX270LC 5, EX280H 5, EX280LCH 5 ARM 9147237 P UB 14 100mm 145mm 100X145 10001 HIT 9180579 ZX270, ZX270LC, ZX280LC, ZX280LCN ARM 9186598 P UB 14 100mm