Johnson Pump 1000GPH Ultima Combo Pump 3/4" Hose Dura Port [07903-00]1000 GPH Ultima Combo Automatic Submersible Bilge Pump 12V Johnson Pump Marine Ultima Combo bilge pumps are JPM's proven Cartridge Bilge Pumps combined with the non clogging electronic switch Ultima Switch for automatic operation. The electronic automatic switch Ultima Switch uses the patented Mirus field effect detector cells producing micro electrical fields that detect disruptions caused by level of water present in the bilge and automatically