Optical specificatoins ? Diameter of the light spot at a distance of 420mm: 20-90mm ? Illumination in 250mm working distance: =75000 1x Adjustable range ? Fluctuation distance: 12.5mm ? Vertical direction of Illumination:±25°adjustable Net Weight ? 70g (excluding headband) Electrical specifications ? Illumination Source: extremely bright light, 5W LED. Life 20000 hours continuous burn. ? Battery: 7.2V Lithium battery (rechargeable) ? Battery Run-time: >2.5 hours ? Voltage: 110VAC/ 220 VAC ? Maximum Power input: 15W ? Electrical Safety Standard: IEC60601.1 class II Type BF equipment. ? Light Source: Our LED lamp without the heat of traditional Halogen headlight. With a color temperature of 6000 Kelvin, this light supplies bright, white, shadow-free light allowing the doctor to see tissue characteristics without distortion. ? Enjoy the flexibility of operating the headlight using the rechargeable Lithium battery, can use without the direct power source. It is one of the most comfortable lightweight headlights and suitable for all kinds of surgery. ? The headlight could be used when it is charging. Has low-battery indicator light. ? Smart design, convenient for mobile diagnosis.