ON THE WAY&reg;8Pcs Button Top High Drain Rechargeable Battery 18650 with Re/Discharging Protection Circuit 3.7V 5000mAh Li-ion Battery Plus Cordless Dual Slot 18650 Charger and Colorful Touch Stylus Pen ON THE WAY18650 5000mAh 3.7V Rechargeable Li-ion Battery have higher capacities than their alkaline counterparts. Light weight and high energy density No memory effect Long storage life Ideal for the following applications:Laptop battery re-building,Flashlights,Custom Lithium-ion Battery Packs.