The Barska 6.5-20x40mm IR Tactical Riflescope is a perfect choice for serious shooters and hunters who are looking for as much control as possible for extreme type shooting. Boasting a fast focus eyeball and side parallax settings, this rifle scope has been designed and engineered for accuracy, reliability and durability. This rifle scope offers a 1 in. single tube construction with an illuminated Mil-Dot reticle in the first focal plane. Locating the reticle in the first focal plane allows the size of the pattern to increase as the magnification is increased. This is preferred by many tactical shooters for use as a point of aim and as a means of measurement. The rifle scope's single tube construction provides high recoil capability with larger calibers. This durable rifle scope is backed by Barska's limited lifetime warranty.