The XT DF has a maximum brightness (primary setting) of 600 lumens, with a secondary light level that's user-programmable at 15, 60, or 150 lumens, or strobe. In keeping with our emphasis on intuitive design and simplicity in our law enforcement tools and training, activation is via a single pressure switch on the tail cap - press once to activate the primary/max setting, twice (''Double Tap'') to activate the user-programmed secondary mode. Setting the secondary light level takes just seconds - simply twist the bezel open to activate programming mode, tap through the levels until you reach your chosen setting, and twist the bezel closed to lock it in. A 3-position twist selector on the tail cap allows choice of intermittent, constant-on or locked. Dual Fuel technology means you'll never be without a power source - it runs with either a rechargeable 18650 battery (included) or 2 CR123A primary (single use) cells, sold separately. The 18650 battery charges inside the flashlight, using the supplied cord and adapters, or any micro USB phone/electronics charging cord - no separate battery charger needed. The XT DF is machined from 6061 T6 aerospace aluminum, type III hardcoat anodized in a proprietary matte black finish. The barrel is wrapped in our exclusive, all-weather foamed vinyl grip. Premium components include Cree XPG LED, gold-plated connectors, polished aluminum reflector and optical glass lens. Includes high-performance ASP 18650 rechargeable battery, battery storage case, retractable charging cord, wall adaptor, car adaptor, adjustable/removable pocket clip, and zippered ballistic travel case.