WHALE 1 x Watermaster IC Upgrade Pack. Watermaster IC Intelligently Controls the submersible pump, for trouble-free operation and peace of mind. Never adjust your pressure switch again. Stops the pump pulsating at high voltages. Stops the pump running continuously at low voltages. Detects when the water container has run dry and turns pump off. Surge damper no longer required. Protects and prolongs the submersible pump. Helps lengthen battery life. Built-in fault diagnostics system. Service free, one-step caibration process. Easily retro-fitted. WHALE Watermaster IC is compatible with a ES1001 & ES5001 WHALE Watermaster pressure switch socket and a EP1612 WHALE Watermaster High-Flow pump only. *Socket Not Included* The water system upgrade caravanners have been waiting for!