Operating voltage: 2.7V-5V Battery options: 18650 battery Dimension: 100mm (length) x 24mm ( diameter) Flashlight body: Aerospace grade 6061 grade aluminum alloy, CNC manufactured to hard-anodized to grade specification type III, anti-abrasive to get solid built body, anti-crash geometry and better heat exchange. Water resistance i.a.w. IP-66 Reverse polarity protection to protect against improper battery installation. HD30B Light Mode: Shutdown status: click white light to low (within 5 seconds), then Double click high light (Click to close in 3 seconds) Click to close again Long : Moonlight mode Long to close Double click under white light highlight: flashing device three clicks: emergency signal four clicks: signal light Double click under white light Low: Long ,Five level dimming(Having memory function) Colour:Black Material:Metal Package Contents: 1 x LED Headlamp 1 x Type C Charging cable Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.