Odec 2 Pack 18-Volt 4000mAh Li-ion Makita Replacement Battery for Makita BL1835 194205-3 LXT-400 BL1815 BL1840 High capacity 4.0Ah Li-Ion battery for Makita BL1830 No memory effect, can be recharged at any time;over-charge and over-discharge protection. CE and FCC certified, tested by manufacturer to match OEM products Our batteries provide plenty of power and last a long time on a full charge. When using this battery, you should pay attention to the use of it. It can not be charged immediately after the battery runs out of power. As you know, the battery is hot after using it, Please set it aside until it cools down, then you can charge it. Otherwise it will seriously shorten the life of batteries.