The ultimate sight for a handgun, the Truglo Tritium/Fiber Brite Site Handgun Sight - Novak 1911 .260/.500 Front Green/Rear Yellow is best installed with the help of a gunsmith. It is made to be lightweight and to fit into a standard handgun holster. The fiber optics technology of this sight allows the shooter to clearly see the target in any light conditions, without the target being able to spot your sight. It is made from sturdy steel, so it can take the rigors of regular use and the elements. Novak LoMount cut .260 Front /.500 Rear (1911 3? Officers & 4.25? Commander .45ACP). Novak LoMount cut replacement sights are designed for 1911-style handguns with existing fixed Novak LoMount dovetail cut slides, however some fitting may be required. Installation by a competent gunsmith is recommended.