FeaturesTitanium Housing QD Absolute Co-Witness MountShake AwakeClear Flip CapsKill FlashMRS (Multi-Reticle System) The HE515GT is a compact 20mm micro optic packed with innovations. Featuring Holosun's Multi-reticle system, the HE515GT allows the operator to switch from a 2 MOA dot to a 65 MOA circle dot with a push of a button. The highly efficient light emitting diodes allow the HE515GT optics to run without a battery in many lighting conditions. Additionally, the CR2032 battery lasts up to 5-years.HE515GT is housed in CNC machined Titanium and comes with removable, non-obstructing, clear flip-up lens covers and kill flash. Holosun's Shake Awake technology puts the optic to sleep with no motion and wakes it up, recalling the last setting with the slightest movement, conserving battery life even further. HE515GT-RD is built for all your needs no matter the weapon platform, environment, or type of use.