Holley EFI universal bypass fuel pressure regulators are for use with fuel systems in street or track applications. They feature adjustable base pressure from 15-90 psi, a gauge port, and a boost reference port as well. The regulators are ideal for vehicles/systems where superior flow and pressure control are desired. The regulators are precision machined from 6061-T6 billet aluminum for strength and durability. They feature a black bright dip anodized body and a clear bright dip anodized top for corrosion resistance and good looks. The Holley 12-894 has -6AN port sizes and the 12-895 has -8AN port sizes.