Small Capacity Rechargeable Batteries – 300mAh / 400mAh / 420mAh Compact Power for Small Electronics These small-capacity rechargeable batteries are designed for low-power devices that need compact, efficient, and long-lasting energy. Available in 300mAh, 400mAh, and 420mAh capacities, they are ideal for use in toys, remote controls, small gadgets, LED lights, mini drones, and more.