This NC STAR ring-style Reflex Sight with red/green dot is powered by CR2032 batteries illuminating a 100% safe for the eyes LED. The weaver and 3/8" Dovetail mount allows for using this optic on a wider variety of rifles. Built from anondized aluminum, this optic is both lightweight and durable. The rheostat dial toggles between different brightness levels for both the red and green LED dot. The unlimited eye relief of a reflex optics allows it to be mounted anywhere along a rail system without having to worry if the dot can be seen. CR2032 Batteries and mounting tools included!