TFO gun sights are the most revolutionary innovation since TRUGLO, Inc. introduced fiber optics. TFO refers to our patented combination of Tritium and Fiber Optic technologies. The Tritium maintains the brightness level of the sight in low-light (or NO light) conditions. That means you can see your sight even in complete darkness with perfect transition through all lighting conditions.

High set fits Glock 20/21/29/30/31/32/37