Hydraulic seal kits come in various types, each designed for specific applications and requirements. Common types include O-ring kits, piston seal kits, rod seal kits, and complete sealing kits for hydraulic cylinders. The variation in design and function means that prices can range widely. For example, a simple O-ring kit might cost anywhere from $10 to $50, while a more complex hydraulic cylinder seal kit might range from $100 to several hundred dollars.