Trijicon, Bright & Tough, Sight, Suppressor Height, Green Front with Yellow Rear, Fits Glock 17/19/22/23/26/27/31/32/33/34/35/37/38/39, BlackTRIJICON SUP NS GRN FOR GLK 9MM YELL: Trijicon Bright & Tough(TM) Night Sights are three dot iron sights that increase night fire shooting accuracy by as much as five times over conventional sights. Equally impressive, they do so with the same speed as instinctive shooting and without the need for batteries. Features : Tritium Phosphor lamp Sapphire window White rings Silicone rubber cushion Protective aluminum cylinders Suppressor sights Back up iron