Flashlight is their daily tool for those who works as ensure public security -and police. A rechargeable battery is their economical choice for their job. We design RT3 -and RT7 with rechargeable lithium batteries. The bulbs keep the advantages of the bulbs for T6A. But make the battery cost much lower if you count that the rechargeable batteries can be used for 500 times. NT18650 that RT series uses is the rechargeable lithium battery with 2000mAh electronic capacity. With the help of the built-in circuit protection, you can use the flashlight freely without worrying the damage of over recharge/discharge. As direct charger -and car express charger are included, you can finish your charging wherever the electronic power you find. MODEL: RT7 MATERIAL: Hard-anodized aerospace grade aluminum 6061 T6 COLOR: Titanium black DIMENSIONS: 193mmX29mm(34mm Head Diameter) BATTERY: 18650 3.6V Rechargeable Lithium battery X 2 BULB: Xenon gas-filled bi-pin bulb LENS MATEWRIAL: Full Clear Glass Lens LIGHT OUTPU: 90 lumens RUN TIME: up to 100 minutes of continues use SWITCH: ON/OFF Batteries Not Included)