The TA648MGO-M240 incorporates dual-illumination technology using a combination of fiber optics and self-luminous tritium. This allows the close in reflexive fire aiming point to be illuminated without the use of batteries. The tritium illuminates the aiming point in total darkness, and the fiber-optic self-adjusts reticle brightness during daylight according to ambient light conditions. This allows the operator to keep both eyes open while engaging close in targets and maintaining maximum situational awareness.