The Holosun HS403B is a red dot offering made by Holosun. This optic features a 2 MOA dot with an amazing 50,000 hours of battery life. This optic has a motion sensor as well as also having a memory function for brightness settings. This optic comes with 10 daylight settings and 2 night vision compatible settings when you are in the manual mode. On the right side of the optic is the battery tray and on the top and right side of the optic are the adjustments for the radical.On the top of the brightness as well as the brightness adjustments. This optic is waterproof and parallax free. Included in the box is the user manual, lens cleaning cloth, tools for installation,a low mount, spare battery tray, the battery as well as also having the lens caps. In the Box Lower 1/3 Cowitness Mount Low Profile Mount T10 L Key Rubber Cover User Manual CR2032 Battery Lens Cloth