This compact and lightweight electro sight is built with a fine 2MOA dot illuminated in red. Attractive and classic anodized matte stainless silver finish. Great for use on pistols and rifles of matching color. Illumination intensity has 11-level adjustments for use under all lighting conditions. Fully adjustable for windage and elevation. Standard 30mm main tube with quick flip open lens caps. Included with the sight is a pair of 30mm vertical split rings for weaver base. The rings can also be used with other 30mm tube scopes. Sight overall length: 5 1/4inch with caps installed; 4 1/2inch without caps Tube size: 30mm Mount center height: 23mm Battery used: CR2032 button cell Package Contents: 1x30SV with rings Flip open lens covers (back and front as shown in the picture) Allen wrench Microfiber Lens cloth 1x 2032 Lithium battery NOTE: Be sure to install the sight on the scope base with light control tower positioned at your left hand side. Vertical split scope ring should be tightened at bottom first and then tighten the top screw.