Replacement Propeller Industrial/Commercial Heavy-Duty Propeller Dia (In.) 30 in Number of Blades 4 Pitch (Deg.) 30 Degrees Blade Material Galvanized Rotation CW Required Motor HP 1-3/4 Required HP @ Higher RPM 1 3/4 hp Required HP @ Lower RPM 1/2 hp RPM Low 720 RPM RPM High 1 140 RPM Max RPM 1140 CFM @ 0.000-In. SP 12 996 CFM @ 0.125-In. SP 12 349 CFM @ 0.250-In. SP 11 651 CFM @ 0.375-In. SP 10 892 cfm CFM @ 0.500-In. SP 10 008 cfm Blade Height (In.) 2 7/8 in