All you need to know in 1 convenient mini study guide.  Study guide includes...Anatomy of the eye, day verses night blind, types of vision, visual deficiencies, dark adaptations, illusions, distance estimations, operational theories & defects, NVG Characteristics & conditions, hypoxia, fatigue, and much more.  Exerts from TC 3-04.93, FM 3-04.203, AN/AVS-6/-10.  Spiral bound and is approx. 5 1/2" x 7 1/2"