The AEG L1215P is a 12 volt PRO Li- Ion replacement battery for AEG 12 volt machines with a capacity of 1.5 Ah. The AEG PRO Li- Ion technology protects both battery & machine in 3 ways: 1) Thermal Overload protection The thermal overload protection constantly monitors the temperature of the battery & automatically safeguards against overheating, therefore increasing the life of the battery pack. 2) Current Overload protection Too much current draw can permanently damage the cells of the battery thus reducing battery life. The Pro Lithium Ion current overload protection automatically shuts the battery down if the current levels get too high, but automatically resets its self so there is no loss of productivity. 3) Individual cell monitoring Individual cell monitoring ensures every cell in the battery is performing to its maximum capability to ensure optimum productivity. The cell monitoring also runs throughout the charge process to make sure no cells are damaged at this time.