Orion 7023 9x50 Illuminated Finder Scope with Bracket Big 50mm aperture, 9x finder scope with illuminated double crosshairs makes it easy to aim your telescope with precision at night, without compromising your dark-adapted vision Contains an adjustable-intensity red LED in the illuminator arm that lights an etched-glass double crosshair reticle Features multi-coated achromatic optics, adjustable focus, 13mm eye relief and a fold-down rubber eyeguard for comfortable use 4.5 field of view finder scope includes aluminum dovetail mounting bracket with spring-loaded X-Y adjustment screws for quick and easy alignment Requires three SR-54 batteries for illuminator operation, included