The RXS-100 Reflex Sight by Bushnell is a high performance red dot sight in a compact package. The RXS-100 is equally at home on pistols, shotguns and rifles, and can be used as a standalone optic or as a close range backup sight to a magnified optic. The reticle is composed of a 4 MOA dot with 8 levels of illumination. When set to the middle illumination level, the RXS-100 can run up to 5,000 hours on a single CR2032 battery and has a 12 hour automatic shutoff. This red dot sight also has a side-loading battery door, allowing the user to replace the battery without having to remove the optic which helps retain zeroing.