The AAA battery is the smaller version of the AA battery ('penlite') and is also known as the mini penlite. Due to its limited dimensions, this battery is perfect for smaller devices.However, the average AAA battery has a lower capacity (expressed in mAh), which means it will last a shorter period of time. Some AAA batteries are rechargeable, you can use a Battery Charger to load them. Please check out the rest of our Batteries & Chargers as well.