Installing valve springs has never been easier. With the help of this tool, it only takes a matter of seconds to remove or install the valves spring assembly in your vehicle. The body is anodized CNC machined 6061 T6 aluminum, for a gorgeous finish and excellent durability. The entire product is made from start to finish in the US. For Ford 4.6L 4V and 5.4L 4V engines. For use on all 4.6L/5.4L 4V Cylinder Heads including Cobra B and C Heads, 03/04 Cobra and Mach 1, Navigator, Ford GT / Shelby GT500 and FR500 Cylinder Heads.