This is a high-flow version of the classic March 809 pump for transferring hot and cool liquids during brewing. It has a max flow of 7 gallons per minute and a max head of 18.6 feet. All the same features and durability as the March 809 pump. This pump is NOT self-priming, the pump head must be filled with liquid before it will pump properly. This means that you will have to position the pump below the level of the liquid for the input. Do not restrict flow into the pump, only on the output side.