Propeller, Replacement, Propeller Dia. (In.) 20 in, Bore Dia. (In.) 5/8 in, Number of Blades 3, Pitch (Deg.) 24 Degrees , Blade Material Aluminum, Keyway (In.) -, Rotation CW Facing Discharge, Required Motor HP -, Required HP @ Higher RPM 1/2 hp, Required HP @ Lower RPM 1/6 hp, RPM Low 1,140 RPM, RPM High 1,725 RPM, Max. RPM 1725, CFM @ 0.000-In. SP 4414/2917, CFM @ 0.125-In. SP 4225/2611, CFM @ 0.250-In. SP 4016/2008, CFM @ 0.375-In. SP -, CFM @ 0.500-In. SP -, Blade Height (In.) 4 3/32 in