The Fuel Pressure Blue Spring is a high-quality replacement part for 2003 - 2007 6.0L Ford Powerstroke engines. This spring is used to increase the fuel pressure in the fuel system, providing a boost in horsepower and torque. It is made of durable materials and is designed to withstand the high pressures and temperatures of the engine. This spring is easy to install and is a direct replacement for the factory part. Install the Fuel Pressure Blue Spring in your engine and experience the difference in performance. With a one year unlimited mileage warranty, you can trust that it's built to last.