These D1spec adjustable fuel pressure regulators are boost referenced and increase fuel pressure at a 1:1 ratio against intake manifold pressure. This replicates the factory fuel pressure regulator and means you will not need to retune you ECU. These universal regulators are fully adjustable and come with a liquid filled fuel pressure gauge, gauge block off plug, 8mm hose barbs and mounting bracket. Suited to NA and turbo charged vehicles! Superb quality, made in Taiwan! Colours vary.