The Sinister Diesel Regulated Fuel Return Kit is constructed of CNC machined billet aluminum parts and stainless steel braided fuel lines with nickel plated fittings. This kit comes with a an adjustable regulator and fuel pressure gauge which allows the user to adjust pressure to keep a constant fuel pressure which will prolong the life of the injectors. Allowing you to upgrade your system with high flow fuel line that integrates right into your factory fuel lines!!! This system is a fully functional package and does not need any additional parts to work. 3/8" inch quick disconnect tool is required for installation.