This Overhaul Kit contains Pistons made of hypereutectic aluminum alloy, which makes the piston inherently stronger. It is also more resistant to expansion and contraction, as well as scuff and corrosion resistant. Efficiency improves due to a better seal between the rings and cylinder wall.Includes: (6) HCTRE23173HC Cylinder Kits (6) HCTAR45723 Rod Bearings (6) HCTAR49243 Main Bearings (1) HCTAR49242 Thrust Bearing (1) HCTAR53625 Head Gasket Set (1) HCTR71918 Oil Pan Gasket (12) HCTR66452 Connecting Rod BoltsThe HCTIK17901HC High Compression Inframe Overhaul Kit, John Deere 6-404D Diesel Engine fits equipment brands such as: John Deere