Truglo fiber optic sight set Glock 20, 21, 29, 30, 31, 32, 37 steel tritium/fiber optic green front, yellow rear. Sight is bright and visible regardless of the lighting conditions. Fiber optics capture and amplify any available light, while a tritium vial provides illumination during complete darkness. Steel construction. Rear sight is adjustable for windage. Three dot sight system with high visibility green front dot, and yellow rear dots. Features:- the ultimate handgun sight- uses patented Truglo fiber optic technology- glows in the dark- uses the brightest tritium available- CNC machined steel construction- concealed fiber cannot be seen by target- fits standard holsters- snag-resistant design".