Function: 1. Remove the lens hood, in the observation state (photos), point the lens at the observed scene and observe the screen from the center of the eye. 2. Adjust the diopter knob to set the most clear image. 3. Adjust the focus knob of the lens to make the observed scene as clear as possible. The device will automatically adjust the screen brightness according to the average brightness of the scene in the center of the screen. Zoom electronic can be realized by pressing the upper and lower buttons, and the range of electronic image magnification is 1 to 8 times. 4. When the ambient light is relatively bright, no additional light source is needed (turn off the additional light source to save battery power). When the ambient light is very dark and the scene observation is not clear, turn on the additional light source and adjust the brightness of the light source to make the observation clear. 5. In the observation state (photo, video), press the "Screen brightness\Auxiliary lighting" button to enter the do menu of the screen brightness adjustment function, the screen, the number when the word "Bright" is displayed indicates the current brightness of the screen. Press the up and down keys, the brightness of the screen changes between the values of 1-9; the value of 9 is the brightest. Specification: Material: plastic; Color: as shown in the picture! Weight: Approx. 610g Size: Approx. 200 x 86 x 56 mm / 7.9 x 3.4 x 2.2 inches Model: NV-300 Magnification: 5X Operating Voltage: 3,7 V Type: Infrared night viewing Lens Diameter: Approx. 42mm / 1.65 inch Effective viewing distance: Approx. 500 meters / 19685,04in Lens Size: Approx. Diameter 40 mm/1,57 inch Field of view: 5°x3,75° Eyepiece adjustment range: ±0,6 Low light observation distance: about 2 meters / 78,7 inch Replaceable battery: battery; Charging power supply: 100-240VAC 0,3A 50/60Hz Output Power: 5V-2000mAa 1. Install the installation Specifications for service updates; battery was supposed to have stock When conducting a session, watch out for positive and traffic directions. 2. (1). Remove the lens hood. (2). Press the button to enter (3 buttons), observe from the loincloth on and see that the internal screen button lights up. Printer machine in normal working condition. 3. Observation of scenery 4. Screen Theatre List of packages: 1 x User Manual 1 x Adapter 1 x do wipe cloth 1 x Canvas Bag 1x USB cable 1 x External Wiring