The Holosun HE507C-GR-X2-ACSS is a new-generation pistol red dot sight packed with features like the multiple reticle system, solar failsafe, and shake awake technology to ensure your reflex sight is always operational when you need it. In addition to two battery-saving techniques, the HE507C-GR-X2 reflex sight offers up to 20,000 hours of battery life on setting 6 with the CR1632 battery. The battery is housed in a convenient tray that slides out, allowing you to easily replace it without removing the optic from your pistol. This model features the revolutionary, patented ACSS Vulcan reticle with an outer circle. It features 7075-T6 aluminum construction with an anodized black finish and fully multicoated glass for long-term durability.