Sight magnifiers are optical telescopes that provide increased magnification to a shooter's view when they are engaged.
They are commonly mounted behind red dot and holographic sights that produce a collimated reticle image.
They are used by police and special operations forces who may use the non-magnified optic for close-quarters combat and utilize the magnifier to engage farther targets.
[4] Hunters may also use them as the increased magnification can aid in target discrimination when prey are difficult to spot in brush or vegetation.
However, there typically is no option to make fine increases or decreases in zoom, as one would be able to with a standard telescopic sight.