Nikko Stirling 30mm Red Dot With 5/8 Integrated MountsDesigned for use on rifles the Nikko Stirling illuminated red dot has also been designed for rifles, muzzleloaders and shotguns using up to 3" shells and handguns up to . 357 magnum cal. Unlimited eye relief and a huge field of view facilitate rapid target acquisition that has helped them gain widespread favour among handgun hunters and competitive shooters. 4 M. O. A plus illuminated Red Dot adjustable 12 position detents brightness intensity control