This 5 HP Gould Pump is a great high volume, low head pump and is the largest external centrifugal pump (non-submersible) that we offer. Has 4" inlet and outlet. 3450 RPM must be field wired as 208/230 volts only. Not self-priming. Use check valve on suction line for self priming applications. Provides a whopping 540 GPM at 20' head, 500 GPM at 25' head, 460 GPM at 30' head, 400 GPM at 35' head. Note: This is Gallons Per Minute, not Gallons Per Hour. One year limited manufacturer's warranty. Weighs 175 lbs.