Flange 4 in Nominal Pipe Size Female NPT 9 in Flange Outside Diameter 15/16 in Flange Thickness Schedule 80 Class Class 150 For Pipe Schedule 80 Polypropylene 150 psi Maximum Operating Pressure -20 Degrees to 150 Degrees F Number of Bolt Holes 8 7 1/2 in Bolt Circle Diameter 3/4 in Bolt Hole Diameter 8 Flange Fitting Threading Black