Fits Ford Powerstroke 6.0L - 2003-2010 - Blue Spring Kit Includes The Following: 1 New Main Regulator Seal/Gasket 1 Upgraded Blue Style Spring (Capable of 60+ PSI) 1 New Plunger with Seal/Gasket 1 New Plunger Seat (optional) 1 New Plunger Seat O-Ring (optional) 1 New Metered Orifice Jet with Seal/Gasket 2 New Regulator House Fitting O-Rings 4 New Bolts 1 New Regulator Housing The “Blue Spring” upgrade is a low-cost, must-have modification that will increase fuel pressure on your 6.0L Powerstroke. Even simple aftermarket performance upgrades can easily challenge the limits of your stock fuel system. Increasing the fuel pressure will help prevent damage to your injectors and even extend injector life. Common pressure increases can be 10-15PSI as well as increased engine performance, increased driveability and smoother power delivery. FEATURES: Easy Upgrade Increased Injector Life Increased Fuel Pressure Great For Stock & Modified Trucks