You missed "A Pair" A pair ofr 6 Volt 230 AH batteries. in series **IS** a 230 amp hour 12 volt battery.. So why are they so much cheaper than say a 4D?The same reason a 10 gallon bucket costs more than a 5 gallon bucket: the 6V is only half the capacity, storing 6v x 230 AH = 1380 watt-hours of electrical energy. The 12v battery is 12v x 230 AH = 2760 watt-hours of energy. The 6v is also half the physical size of a 12v with the same AH capacity - see Ex-Calif explanation of the lead plates. A 6v battery requires only 3 cells, while a 12v requires 6. Lead is actually quite expensive, so doubling the amount of lead plates (6 cells vs 3 cells) nearly doubles the production cost of the battery.