Curb Cap For Fan Diameter 30 in For Fan Type Tubeaxial Mounting Hole Diameter 1/2 in Material Steel Body Diameter 38 in Bolt Circle Diameter 30 1/2 in Compatible Curb Grainger Part Number 2RB81 4HX43 4HX51 Finish Baked Enamel For Use With 3C412 4TM86 Maximum Inlet Air Temperature 200 Degrees F Metal Material Thickness 1/2 in Overall Height 6 in Overall Length 42 in Overall Width 42 in Product Type Curb Cap