AmeriGlo brings a clear advantage to your shooting experience on and off the range. The original standard in self luminous night sights, the Classic 3-dot design is the most popular among personal defense, military, and law enforcement. It is machined of steel and utilizes Swiss-made tritium light sources. This model has green tritium with white outline and a black frame. It is compatible with S&W M&P Shield excluding S&W M&P Shield 380 EZ.