For instance, there are two saltwater air-conditioning systems with two AC circulation pumps. There are a pair of freshwater Headhunter pumps, one 110-volt and a backup 24-volt DC unit. Two power steering pumps and a pair of heavy-duty pumps from the power-takeoff on the transmissions can drive the Wesmar nine-square-foot fins, as well as both 33-horsepower bow and stern thrusters. The automatic oil-change system services the mains, the 23 and 15 kW Kohler gensets and both transmissions. There are eight 115-amp AGM marine batteries in boxes for the house system, a pair of 200-amp, boxed AGM starting batteries per engine and a 100-amp heavy-duty battery, also boxed, for each genset. Then there are a pair of shore-power isolation transformers with ISO boost, two 75-foot Glendinning Cablemasters and a 4 kW inverter. Combine that with sturdy, no-nonsense construction and the Endurance 680 more than lives up to her name.