This Leeson commercial duty enclosed ball bearing motor is designed for mounting directly to fan column. Thermal overload protection. 4 mounting studs are extended 1/2 in. on 5.14 in. bolt circle. Split phase. U.S.A.HP 1/2 Rated RPM 1,750 Volts 115/230 Amps 4.6 at 115 Volts Hertz 60 Motor Phase(s) Split Shank Diameter (in.) 1/2 Frame Type NEMA 48Y Totally Enclosed Housing Yes UL Recognized CSA Recognized. * Permanent split capacitor design eliminates centrifugal switch for 3-phase reliability * Energy efficient dual voltage design, 115 or 230 * Thermal overload protection * Heavy-gauge steel yoke welded to frame.