Borgeson 800209 Power Steering Box, Delphi 600, 12.7:1 Ratio, 3/4"-30 Spline New Delphi 600 series power steering box with a 12.7:1 ratio. Power Steering Box, Delphi 600, 12.7:1 Ratio, 3/4"-30 Spline Made in the U.S.A. since 1914! Official steering components of the National Street Rod Association Industry leading warranty & support