The functional differences are that silver oxide batteries typically have 50% greater capacity than alkaline chemistry, relatively slowly declining voltage during discharge compared to alkaline types of the same size, and superior leakage resistance. The ultimate energy capacity of a silver battery may be as much as twice that of an alkaline. Also, a silver cell with a flat discharge characteristic is preferable for devices that need a steady voltage, such as photographic light meters, and devices that will not operate below a certain voltage; for example, some digital calipers, which do not work below 1.38V.