A bypass-style fuel pressure regulator for injected engines, ported with one AN6 and two AN10 connections. The bypass design is what makes it suitable for EFI: rather than restricting the feed, it maintains rail pressure by returning surplus fuel to the tank, which keeps pressure stable when the injectors close and prevents the spikes that upset fuelling and stress the pump. The twin AN10 ports handle a high-flow feed and return, with the AN6 typically taking a smaller line, so the regulator suits systems running serious pump capacity rather than a modest street setup. Set base pressure with a gauge fitted to the regulator, and mount it after the fuel rails wherever the layout allows.