BUS1075 Features: * The FastFire II provides the only fully waterproof unit in its product category * The FastFire sight is very small, mounts very low, and weighs a mere 1.6 ounces * And it has repeatedly proven it""s toughness on the slides of high power semi-autos, on slug guns, on shotguns and on high power rifles * The FastFire housing is made of metal for strength and durability * It""s lenses are precision ground and polished to exacting geometries to virtually eliminate parallax and to provide a very clear crisp sight picture * It is fully windage and elevation adjustable and lockable * It features both an on or off switch and a light sensor that automatically adjusts the dot""s brightness to the available light * FastFire is powered by a lithium CR2032 battery, which is commonly available and long lasting because of the highly efficient electronics and the battery-saver mode * A battery can last as long as five years * The Picatinny Mount allows mounting on just about any rifle * Special bases are available for the most common firearms Includes: * The included plastic hood covers the light sensor and puts the unit in sleep mode when the on or off switch is set to ""on""