The Holosun ARO (Advanced Rifle Optic) takes everything shooters love about the 403 and 503 series and improves it with a stronger housing, larger 22mm window, and a new 1.63" lower 1/3 co-witness mount designed to pair seamlessly with Holosun magnifiers. Compact, lightweight, and rugged, the ARO delivers crystal-clear glass, long-lasting power, and the flexibility of Holosun's Multi-Reticle System (MRS), letting you switch between a precise 2 MOA dot and a fast-acquisition 65 MOA circle-dot reticle. Ideal for carbines, tactical rifles, and hunting setups, the ARO ensures quick target acquisition, excellent durability, and confidence in all conditions with Shake Awake technology, IP67 waterproofing, and a 50,000-hour battery life.