Perfect for shooters who demand fast target acquisition, rock-solid reliability, and rugged durability. Powered by easy-to-find AA batteries, the Model 512(TM) is the most popular HWSA(R) in the lineup-ideal for those who don't require night-vision compatibility but want uncompromising performance in any environment.Specifications and Features: L x W x H: 5.6" x 2.0" x 2.5" (142.2 x 50.8 x 63.5 mm) Weight: 11.5oz (326 g) Mount: 1" Weaver or MIL-STD-1913 rail Windage & Elevation Adjustment: 0.5 MOA per click Night Vision Compatibility: No Brightness: 20 daylight settings Power Source: 2 x 1.5 V AA batteries - Supports lithium, alkaline or rechargable Country of Origin: Made in USA