The cylinder head repair kit is designed to be compatible with the entire range of Honda Ranger 420 (TRX420) four-wheel all terrain vehicles, covering a wide range of models and configurations from 2009 to 2020, including TRX420FA, FE, FM, TE, TM, etc. It is also compatible with ES (electric start), DCT (automatic dual clutch), EPS (electric steering), and IRS (independent rear suspension) versions. The corresponding part numbers of the kit components (such as cylinder head 12310-HP5-L10, gasket 12315-HP5-601, etc.) ensure precise matching with the engine. It includes a complete cylinder assembly, cylinder head, and gasket kit, designed to solve common problems such as cylinder pressure drop, seal failure, oil burning, or engine overheating, helping to restore engine performance and reliability. It is suitable for maintenance or engine reconstruction projects.