This EOTech 300 Blackout Holographic Weapon Sight offers a 2-dot ballistic drop reticle that allows the shooter to zero either subsonic or supersonic rounds in the same reticle pattern. Reticle: .300 BLK Zero Dimensions: 3.8?L x 2.1?W x 2.5?H (97 x 54 x 64mm) Weight: 9.0 oz / 255 g Water Resistant: Submersible to 10 ft./3 m Mount: 1? Weaver or MIL-STD-1913 rail Brightness: 20 settings Power Source: (1) 123 Lithium battery Battery Life: Approximately 600 continuous hours at nominal setting 12 at room temperature