Centrifugal Inline Duct Fan Housing Material Galvanized Steel Fits Duct Dia 8 In. Voltage 120V Max Amps 0.50 Max Wattage 71 Number of Speeds 1 Housing Dia 13-3/8 In. Length 8 In. Motor RPM 2545 CFM @ Duct 390 CFM @ 0.000-In. SP 428 CFM @ 0.125-In. SP 405 CFM @ 0.200-In. SP 410 CFM @ 0.250-In. SP 380 CFM @ 0.375-In. SP 357 CFM @ 0.400-In. SP 390 CFM @ 0.500-In. SP 334 CFM @ 0.600-In. SP 353 CFM @ 0.750-In. SP 285 CFM @ 0.800-In. SP 314 CFM @ 1.000-In. SP 239