A Assembled/Unassembled: Unassembled , Base Height: 1.75" , Base Length: 50.5" , Base Width: 50.5" , Bearing Type: Regreasable Pillow Block , Blade Dia.: 42" , CFM @ 0.750-In. SP: 14,105 , CFM Range: 12,446 to 32,495 , Drive Type: Belt , Housing Material: Galvanized Steel , Max. Inlet Temp.: 120 Deg.F , Mounting Location: Roof , Overall Dia.: 52" , Overall Height: 38" , Propeller Dia.: 42" , Propeller Material: Steel , Requires: Roof Curb For New Installations , RPM Range: 275 to 718 , Shaft Dia. Sheave End: 1 1/4" , Speed Controllable: No