500 GPH 12 Volt Cartridge Aerator Pump | Johnson Pump 38503 Johnson Pump 90 degree cartridge aerator pump fits many small livewell or baitwell needs. 90 degree inlet model 500 gallon per hour flow rate 12 volt DC operation Easy to change twist lock motor cartridge Small profile fits in confined spaces Long life water cooled motor Glass resin composite impeller 3/4 in. O.D. discharge port 3/4 in. NPS straight thread Includes crack resistant Dura Port fittings Unique anti-airlock feature 3 year warranty