A monocular is an NV product that has one eyepiece and one objective. A NV monocular has many advantages and is one of the most versatile night vision devices. They are typically thought of as hand held units; however many can be head mounted as well as weapon mounted. One of the major benefits of a monocular over a binocular or biocular is the fact that you always have one eye that is adjusted to the ambient lighting conditions. This is particularly useful for users that might constantly be moving from dark conditions to lighter conditions where night vision might not be required.