Helix External PumpIdeal for koi ponds, external filters and low head water falls, these reliable pumps are a great value. Continuous duty, weatherproof motors can be used outdoors without additional protection from weather Super quiet operation 8 power cord included Not self priming use in flooded suction applications or with check valve on suction line to maintain prime All sizes (except HEX3600) have dual voltage motors, pumps are shipped 115v but can easily be field