The SPI SPARK extra long-range infrared illuminators provide advanced image-intensified viewing capabilities to night vision devices, and is ideally suited for operations in little to no ambient light. The illuminator features adjustments for field of view divergence and output power, extending the capabilities of night vision device. One of the market’s most powerful infrared illuminators, the SPI SPARK comes equipped with the 18650 rechargeable battery and charger. The Sioux line includes the Sioux 850 model with 850nm peak wavelength and Sioux 940 model with 940nm peak wavelength. The 850 nm wavelength is standard for most night vision applications. The 850nm light source does produce a faint red glow at direct exposure, but otherwise it is not visible to the naked eye.