Product: Goulds Three Phase (230/3/60 and 460/3/60) 3 HP 3500 RPM Pump. Model Number: 3ST1H2CPR2 Formerly: 3ST1H2A4, 3ST1H2APR1, 3ST1H2C4, 3ST1H2D4 Impeller Diameter: 4.75"