DUAL GAS FEED FUEL LINE WITH FUEL PRESSURE GAUGEFits Holley w/8-21/32" centers. These fuel lines are not only great looking but are very functional. They incorporate a small, convient 1-1/2" diameter fuel pressure gauge. The gauge is designed to read in  1/2" lb increments and has a range of 0-15lbs. Inverted flare female inlet thread size 5/8-18.