A carbon-zinc battery is a primary battery (non-rechargeable)
commonly used in low drain consumer applications, such as clocks, calculators,
and garage door openers. Carbon-zinc batteries are available in the same
sizes as the alkaline and manganese dioxide ("AA", "AAA", 9-volt, "C", "D")
varieties. They are one of the most widely used dry primary batteries because
of their low cost and reliable performance.