Flange 4 in Nominal Pipe Size Grooved 4 1/2 in Flange Outside Diameter 3/4 in Flange Thickness Ductile Iron Zinc Plated 300 psi Maximum Operating Pressure -20 Degrees to 180 Degrees F Number of Bolt Holes 8 7 1/2 in Bolt Circle Diameter 3/4 in Bolt Hole Diameter