The Primary Arms MRSC Micro Reflex Sight now comes with Autolive technology. This feature turns off after sitting still and will automatically turn on at the slightest motion helping to conserve battery life. The Micro Reflex Sight is optimized for compact and micro compact pistols for concealed carry as it features a slightly smaller 21mm lens to keep the profile as slim as possible when mounting on smaller pistols eliminating any overhang on the slide. Even though the lens is smaller than the mini, the square profile offers an unobstructed field of view allowing you to have a clear sight picture every time you present your pistol.