The Holosun Enclosed Pistol reflex Sight with Red Dot System is a pistol-sized optic with an enclosed frame for vibrant sight picture, clear glass and Titanium housing. It is powered by a CR1632 battery and Holosun's innovative Solar Fail-safe back up. The HE509T-RD allows the operator to switch the reticle between a 32 MOA circle with 2 MOA dot, a 2 MOA dot only, and a 32 MOA ring only with the push of a button. The same LED projects all three reticles, so no re-zeroing is necessary. It comes equipped with Holosun's Shake Awake technology with last setting recall.