The SURE-FIRE M1 uses an 830 nm wavelength Infra-Red diode and produces substantially more Infra-Red light than produced by a flashlight with an Infra-Red filter. It also runs for more than eight hours on a single DL123A lithium battery, making it very economical to use. Because of its substantially higher InfraRed light output, and the fact that the human eye still has some sensitivity to the shorter wavelengths of Infra-Red light, the M1 will have a distinctly higher "signature". The M1 utilizes a lens to focus the Infra-Red light into a round beam about 12 degrees wide. This produces a spot about 5 feet in diameter at 25 feet, 10 feet at 50 feet, 20 feet at 100, and so on. This is a much narrower and farther reaching beam than produced by the IR light source typically built into military night vision goggles, such as the AN/PVS-7B. It is wide enough, however, to still be useful at short distances, while providing useful illumination up to as far as 100 yards. It is a very useful tool to have when using night vision devices. If you use night vision goggles or similar devices, there will be situations where you won‘t have enough ambient light to form a good image of what you are trying to see.