Pelco’s LL27 Series infrared illuminator is designed to be used with low light level cameras with sensitivity in the IR spectrum (above 700 nm) for nighttime surveillance when a minimum of visible illumination is required. An IR “covert” filter transmits approximately 0.01 percent of the visible light spectrum. Automatic on/off operations are controlled by a photocell with a time delay feature that prevents the unit from being switched off by a momentary beam of light such as that from a headlight. This rugged weatherproof unit is equipped with a built-in sun visor, quick-release latches for ease of service, and sturdy mounting cradle.