Attwood Tsunami bilge pumps. Cartridges are replaceable/interchangeable without any tools. Tsunami’s efficient design circulates water around the pump motor housing, helping to absorb the heat given off by the operating motor. Pump has the best quality bearings and brushes,alloys and magnets. Patented shaft seal centers directly on the motor shaft, preventing leaks caused by misalignment. Exclusive molded wirings prevent water damage and resist corrosion.