Now when you buy a battery, you will see AA or AAA logo on the battery label and paper card. What do you mean by that? What is the AA battery?
In fact, AA, AAA, C, D, etc. are all descriptions of the battery model. For example: AA is what we usually call the No. 5 battery. The general size is: 14mm in diameter and 49mm in height. AAA is what we usually call the 7th battery. The general size is 11mm in diameter and 44mm in height.
The C model is also the second battery, which has many uses. The standard C (flat head) battery has a height of 49.5±0.5mm and a diameter of 25.3±0.2mm. D model is the first battery, widely used, civilian, military, special DC power supply can find D-type battery, standard D (flat head) battery height 59.0 ± 0.5mm, diameter 32.3 ± 0.2mm.
With this explanation, everyone understands what these English letters on the battery pack mean. After buying the dry battery, you can see at a glance, no more confusion.
