Adopting the latest American Cree XML LED, the Fenix TK21 is the first high intensity, compact outdoor tactical flashlight to use an XML LED with the side mode switch button. Fenix TK series tactical LED flashlights feature a robust exterior design that has type III hard anodized finish to avoid scratches and waterproof to IPX-8 standard. Powered by two CR123A batteries or one 18650 rechargeable battery (Li-ion), this LED flashlight features multiple brightness levels and is a perfect combination of extremely high intensity (468 Lumens on turbo setting) and ultra-long runtime (220 hours on low). The Fenix TK21 tactical LED flashlight is your reliable partner for all of your outdoor adventures. LED Lifespan = 50,000 hrs