Pin point aiming - HiViz Flame Sights

Brightness plus real reason I purchased was because the smaller diameter optic permitted more accurate placement of shotgun slugs out to 100 yds for 3Gun competition. Fit is great, width fits my M3000 rail perfectly, no gap between sight bottom and rail (second screw on opposite end would have been a big plus although I would have to drill and tap for the second screw). The sight comes with four or five different screws to fit various factory holes. I simply remove the factory sight and screw on the HiViz. Bought both the green and red as they were so inexpensive.