4 Gallon Salt Feed Tank with 12V PumpThe Four Gallon Salt Feed System with Pump is designed for boats that operate in fresh or brackish water and can only be used with the Lectra/SanA(R) MC(TM) or electro-scan(TM) Type I MSDs. The unit&&';;s Control Panel monitors salinity and salt solution will automatically be added to the MSD when needed. Pressurized freshwater is required-a minimum of 15 psi (103 kPa) working pressure.The simple and basic operation of the system is as follows: the system needs salt water to operate properly and salt can be added when not in full seawater conditions. When the system is activated the electrical charge applied to the patented plates generates the disinfectant to kill viruses and bacteria. As that disinfectant is generated the high-speed macerator breaks apart the waste allowing greater contact between waste and disinfectant. If your toilet uses freshwater we recommend considering the Purasan. Specifications: Type: Holding Tanks Box Dimensions: 11"H x 11"W x 18"L WT: 6.3 lbs UPC: 085462044687