My dear friends.<br />Because it is a high power flashlight.<br />Strict in voltage.<br />I suggest you use 4 * 26650 battery.<br />Since 26650 battery voltage is more stable.<br />Can more bright led flashlight.<br />You can use a 4 * 18650 battery.<br />But need the actual capacity of more than 1500 ma.<br />If you use inferior 18650 battery.<br />Cannot start the flashlight.，<br />Please understand.<br />thank you<br />Packing:<br />100% Brand New<br />1 x 24*XM-L T6 LED 35000lm flashlight<br />4 x Plastic pipe<br />Please note: the packing does not include the battery.<br />If you need to battery， need to buy another.