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 Glock 17,19,22,23,24,26,27,33,34,35,37,38,39 Gen1-4.