At the core of the Pulsar Challenger GS 3.5x 50mm is the unique combination of specially designed optics and the CF-Super Image Intensifier Tube which ensures the highest edge-to-edge resolution, clear, distortion-free and geometrically precise image across the entire field of view. The body of the device is hermetically sealed which enables use in inclement weather (fog, heavy shower, dusty environment, sand storm etc.). The Challenger GS 3.5x 50mm is equipped with a powerful infrared illuminator that can be used in insufficient illumination conditions for observation at above average distances. The device and the built-in IR illuminator are switched on/off with a single switch. Design of the switch prevents the IR illuminator from accidental activation (to avoid disclosure of the observer).