Carolina EDC Reviews talk about sights used on the MP5 and UMP series from Heckler & Koch... "Standard Dot front sights use a patent pending glow dot that absorbs light and glows in low light levels before it is dark enough to see the tritium. Green is a great option for low light and has a very bright glow intensity. The surface area of the convex dot increases light absorption, intensifying the charge of the glow properties of the dot.

Kit Includes: front sight, rear sight (if applicable), screw kit (if applicable), hex wrench, front sight tool (if applicable), blue threadlocker, insert with instructions."