The Holosun AEMS CORE combines a large field of view in a compact" lightweight package of core features that create an incredible value for the consumer. The AEMS CORE has double the glass surface area and is 11% shorter than standard 20mm micro style optics and weighs just 3.9oz without a mount. The AEM CORE features of the CORE model include a cast aluminum housing" Shake Awake" 2MOA dot reticle" and up to 50k hours of battery life. The included lower 1/3 co-witness mount is removable providing adaptability across multiple firearms platforms. One CR2032 lithium battery is included.