The Big John submersible sump pumps provide efficient; trouble-free service for extended or continuous use in moving large volumes of water. A choice of manual or automatic versions with various switch configurations provides the user the right pump for their needs. Little Giant's submersible sump pumps are ideal for use in Excavation; Crawl Space; Basement; Underground Passageway; Loading Docks; Grain Elevator; Construction Site; Cooling Tower; Fire Cleanup and other applications requiring high volume water dispersal. Fluid Systems Design Parameters * Cast bronze or cast iron pump housings with protective epoxy coating for corrosion and rust resistance. * Oil filled motor housing for lifetime lubrication and rapid heat dissipation. * Stainless steel screws, bolts, and handle. * Mechanical seals (stainless steel spring, nitrile parts, carbon and ceramic faces). * Thermal overload protection. * Manual and automatic models. * Automatic operation with pressure switch operates when water level is between 7" to 10". Pump shuts off when water level falls to between 1" - 4" (Pressure switch is non-adjustable).