The Duracell Ultra AAA battery demonstrates itself as being one of the most cost effective disposable batteries designed for general use. You will not need to replace it as often as you might when using a basic Duracell AAA battery or a Duracell Plus AAA battery as this holds 40% more power than the Duracell Plus AAA battery. Its durability and high power retention means the Duracell Ultra AAA battery is the most economical of choices.