Product OverviewFenix TK21 U2 Special Edition !Adopting the latest American CREE XM-L LED, TK21 is the first high intensity and compact out door flashlight using XM LED with the side mode switch button. Fenix TK series flashlights feature a powerful, tough and waterproof to IPX-8 Standard design, which is suitable for various outdoor environments. Powerered by tow CR123A batteries (Lithium) or one 18650 reachargeable battery (Li-ion), with multiple brightness levels, the light makes a perfect combination of the xtremely high intensity and the ultra long runtime. Therefore, TK21 must be your reliable partner when searching, rescuing, etc.