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, Black GL201-C-600651 TRIJICON 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.